All Stories

2012

The story has to begin with the 2012 regional contest. The fact that I entered at all was something of an accident.

I had started competitive programming in high school, also by chance. A teacher came to promote it to our class with stories of exceptional students who competed internationally, earned full scholarships worth tens of thousands of dollars, and were admitted to Princeton. Our provincial contest cost about 30 yuan to enter. He reduced the proposition to one memorable line: pay thirty yuan, earn three hundred thousand.

So I signed up, became absorbed in it, won a silver medal at the national competition, and secured admission to Shanghai Jiao Tong University.

I knew what caliber of student attended SJTU; many were far stronger than I was. Its ICPC team was stronger still, with several world championships behind it. I therefore entered university with no intention of continuing. I clearly had no chance.

That changed when I arrived in the United States in 2012. I was in a 2+2 program: two years at SJTU, two at the University of Michigan, and degrees from both. I came to Michigan as a junior. Michigan had just placed second and won gold at the 2011 World Finals, the best result in school history, and the department displayed the achievement prominently in its main building.

I noticed it and moved on. My roommate saw an opportunity. SJTU was formidable, he reasoned, but perhaps Michigan was not. He investigated and discovered that the 2011 team—qualified through the 2010 regional—had depended on two extraordinary contestants: one later retired and became our student coach, while the other was a one-semester exchange student and former member of China’s IOI team. Neither remained eligible afterward. Without them, the program collapsed and did not even reach the 2012 World Finals.

My roommate read the 2011 regional problems, studied the standings, and reached a simple conclusion: he could do this too.

The contest required teams of three, so he approached me with the one line that worked: “Don’t you want another chance at that dream?”

He produced the 2011 problem set. This one was trivial, he said. So was the next. We examined six problems, all apparently easy. “See?” he said. “That’s qualification right there.”

I joined him.

Our team selection that year took several turns, then broke altogether.

Before the internal qualifier, we asked the coach how teams would be formed. Could the two of us lock ourselves into one team? No, he said. For fairness, the top three would form Team One, the next three Team Two, and so forth. Did that mean we had to manipulate our scores?

In practice there seemed little reason. We had placed first and second in every practice contest before the qualifier.

Then the qualifier went badly. My roommate had grown overconfident and spent too long on a difficult problem, leaving several easy ones untouched. Worse, the qualifier ran on two days over a weekend, and contestants could choose either day. We both competed on day one. Even after his mistakes he remained second, so all seemed well. On day two, however, two unexpected contenders appeared. Neither had attended any practice, so we had not known they existed. Both passed him easily.

The plan fell apart. I would apparently team with those two, both Chinese international students. I did not particularly mind, but for my roommate it was the familiar story of asking a friend to accompany you to an audition, only to watch the friend get the part.

I finished first with 7 problems, the next two solved 6 each, and my roommate solved 4. The gap was too large to challenge unless one of the others withdrew voluntarily.

Neither did. I joined them instead. I will call them my problem-reading teammate and my passenger teammate. The first would become the teammate who concentrated on analyzing problems during our two World Finals appearances, although at this point he still did plenty of implementation.

The passenger teammate supposedly had a considerable reputation in high school and was once spoken of alongside Cao Qinxiang, winner of China’s 2008 National Olympiad in Informatics. That sounded formidable.

He then let us down on a truly impressive scale.

Before the regional, we heard that our region would receive a wildcard. We believed it normally sent three teams and would therefore send four. Its three leading programs—Carnegie Mellon, Waterloo, and Toronto—were exceptionally strong. The first two regularly approached the World Finals medal positions; Toronto, we heard, had a former national IOI team member that year.

Those three were elite not merely within the region but throughout North America. Waterloo and CMU frequently finished as the top North American school at the World Finals. The balance changed only later, when MIT attracted a number of strong Chinese contestants.

Judging from World Finals results in those years, North America was a comparatively weak region: stronger than Africa, the Arab region, and South America, but well behind Europe and Asia on average. Within that weaker region, ours was among the strongest.

We thought the wildcard solved everything. Remove the three established powers and we were the obvious next choice; the other schools that year did not appear competitive.

We were relaxed, concerned only with preserving fourth place. We did some university-organized practice but nothing extra. I barely knew my new teammates.

Contest day brought nine problems, of which the first eight were straightforward. They still required some code. By World Finals standards the implementation was negligible, but our coding was ordinary then, and we spent considerable time on those easy problems. CMU solved the first six in ninety minutes and reached eight around the three-hour mark, finishing everything before the scoreboard freeze.

My problem-reading teammate and I needed more than four hours to implement and debug six. Meanwhile, the passenger teammate began with the final—and hardest—problem. Problems are not normally arranged by difficulty; by coincidence the last one was hardest, and by coincidence he read in reverse order.

It was geometry. With any experience, we would have recognized it as the sort of deliberately formidable regional problem meant to keep the strongest teams occupied. Our teammate was extremely confident, declared it manageable, and began coding. He produced a program of just over 60 lines near the start and failed to debug it for the rest of the contest. No surprise: the official solution required more than 200 lines of case analysis. Sixty lines were unlikely to cover it.

It consumed much of our early computer time. Midway through, he abandoned geometry and moved to Problem 7, another easy one involving currency conversion and shortest paths. The catch was that floating-point arithmetic introduced too much error; fractions had to be maintained with 64-bit integers. He used floating point and failed again.

An hour later, the problem-reading teammate recognized the issue and rewrote it with fractions. It still failed. We solved neither problem. Afterward we discovered that one array had simply never been initialized. Set it to zero and the solution passed.

Problem 8, the only one I never even read, was basic network flow. I could have solved it. The contest never gave me the chance: all our computer time went into debugging the other two.

We finished with 6. CMU completed the set; Waterloo and Toronto reached 8 around three hours but did not finish everything.

In the postmortem, the passenger teammate suddenly realized he had effectively contributed nothing: two attempted problems, neither accepted, zero additions to the score, and a great deal of computer time consumed.

My roommate competed on Team Two and had an even worse day. One teammate was an American whose name, rendered phonetically in Chinese, sounded rather unintelligent. We had thought little of it beforehand. After the contest my roommate was furious, and the unfortunate implication of the name became the man’s permanent nickname in our stories.

My roommate knew his team was essentially along for the ride, so he did not take the contest very seriously and spent much of it coaxing this teammate through code. The experience was startling: algorithms went unexplained and implementations went unwritten, painful to watch at every turn.

We placed eighth overall, behind four CMU teams, two Waterloo teams, and one Toronto team. Looking at that list, qualifying might itself have been awkward.

After a month of waiting, we learned that we had not qualified. Our region did not normally have three places after all; it had two, and the third was already the wildcard it regularly received for being strong. There would be no fourth.

Misfortune can conceal good fortune. In retrospect, not qualifying spared us a World Finals appearance in which we would merely have made up the numbers. The passenger teammate was no longer eligible after that season. The problem-reading teammate, my roommate—now the mathematics teammate—and I decided to train properly, compete seriously, and stop treating the World Finals as merely a vacation.

This was alarming. We had only wanted a trip. How had we suddenly acquired ambition?

I could not have imagined how much further my relationship with the World Finals would extend.

In early 2013, the latter half of that season, the three of us trained frequently with others from Michigan. CMU’s student coach and ours were friends and both served on the USACO committee, so we often trained at CMU, occasionally alongside members of the U.S. IOI team, who demolished us. We had entered no official contest as a trio, though we had done many informal ones. The difficulty with informal practice was that our roles remained casual: whoever felt like coding did so. We had not yet settled into the roles that would later define our problem-reading and mathematics teammates.

Searching through emails more than a decade later, I found this ancient photograph sent by our assistant coach.

2013

By 2013, it was time to contemplate score management again. After more than half a year of serious, if hardly relentless, training, our fundamentals were vastly stronger.

Would unexpected rivals appear? We did not know. None did, and given what we knew of the school, none should have. All three of us had earned first prizes in Chinese provincial informatics competitions. Against students who began programming at university, there was little reason for us to lose.

We passed the internal qualifier safely in the top three. One newcomer with astonishing typing speed stood out: he implemented 3 of 7 problems faster than either teammate. But speed was his limit. He finished with 4 while each of us solved at least 5.

At the regional, our goal was qualification; our coach’s was beating Waterloo. Michigan had once taken World Finals silver ahead of Waterloo but had never beaten it at the regional, and Waterloo was consistently strong. The coach had made this a longstanding objective.

We still allocated implementation almost at random. The problem-reading teammate coded at least two solutions and, after finding his own disastrous bug, passed a simulation problem. The mathematics teammate stared at the final problem, I, an easy one, wondering whether intermediate values could exceed 18 digits and require big integers. When another Michigan team passed it, we knew big integers were unnecessary: we knew their level, and they certainly could not implement them. He took over and passed almost immediately.

We discarded Problem G, a geometry problem, on sight. Was this meant for human beings? That was the correct decision. The judges’ implementation was nearly 300 lines. The contest later appeared on Codeforces for the world’s strongest contestants to attempt; ten years later, nobody had solved it within five hours.

The main drama was Problem E, a network-flow problem whose modeling was already difficult. When the problem-reading teammate and I found the formulation, it was deeply satisfying. We coded it, submitted, and timed out. We replaced the initial linear search with binary search, submitted again, and still timed out.

The margin seemed substantial. Each submission took five minutes to return, suggesting a genuinely long run.

We ran out of ideas. With linear search, we knew in theory that the graph need not be rebuilt each time; one could continue augmenting the existing graph. We did not know how to implement that, though it was probably the intended solution.

With 12 minutes left, we tried speculative and constant-factor optimizations and submitted frantically. Judging was so slow that every submission remained queued.

About five minutes before the end, one passed—the submission from seven minutes earlier. By then, countless later attempts were stuck in the judging system. When the acceptance appeared, all three of us shouted loudly enough for the room to hear. Someone applauded, then others joined, and soon contestants across the hall were applauding us.

It was a remarkably friendly response. They did not even know what had happened; accepted submissions after the scoreboard freeze were not displayed.

We qualified in second with 7 problems, tied with first on solved count. We also beat Waterloo—and pushed them into fourth, out of the World Finals entirely. Later we learned that even without the final acceptance, we would still have qualified and remained second in the school standings, which rank only each school’s best team. We had been safer than we realized.

Training that year remained much like the previous year: team sessions when schedules allowed and individual work otherwise. The problem-reading teammate and I took a graduate algorithms course, one of the hardest courses most students encountered. I later spent five years as its teaching assistant during my PhD and came to understand that very well.

At the time, however, we treated it as an easy elective. We sat at the back discussing World Finals problems, barely listened, and both earned A+ grades.

We also entered NAIPC, the North American Invitational Programming Contest. Its predecessor was the University of Chicago invitational the previous year; now renamed, it invited North America’s World Finals qualifiers to compete. It was not an official qualifier. After North America’s contest structure was reorganized, it gradually evolved into NAC and entered the formal qualification system.

That year’s NAIPC was lavish. The venue was a grand library reading room that looked remarkably like Hogwarts. Competing together in person was excellent, and the prize pool aspired to World Finals scale: $12,000 for the champion, $6,000 for second, and $3,000 for teams in the silver award tier.

We placed fourth, received a silver award, and collected $3,000—the first and only prize money of my competitive career. Our timing was fortunate. The prize pool collapsed over the next few years, eventually becoming a $250 Amazon gift card for a gold award. Apparently the first year had consumed the next decade’s budget.

There were 21 teams. Our region’s three World Finals qualifiers placed third, fourth, and sixth. Within North America, our region really was exceptionally strong.

I remember little of the contest itself beyond passing our last problem around three hours and then knowing nothing else for the remaining two.

Before the World Finals, I returned to SJTU to graduate while both teammates stayed in America. That was the end of organized preparation; we did no serious training.

2014

A new season began. Having learned from the previous World Finals, we had to train properly. We had been far too casual.

How had this become more serious every year?

Human appetite is endless. Once something is attained, one wants more. We began merely hoping to travel to the World Finals; now we wanted a medal.

Team selection brought a new complication. I had graduated and begun a PhD. Many strong classmates from SJTU also came to Michigan for graduate study. More worrying, the mathematics teammate discovered that a graduate student from National Taiwan University had won World Finals gold and was Codeforces red-rated—among the platform’s elite. We called him the red-rated star.

If he competed, one of us would certainly lose a place.

Fortunately, we met him at the information session and learned that he was no longer eligible. We relaxed.

None of the other strong arrivals from SJTU entered either. The three of us again swept the top positions and stayed together.

The regional was anything but calm, though the result was never seriously in doubt. After its Waterloo the previous year—apparently ending a very long streak of World Finals appearances—the University of Waterloo returned seeking revenge and won with 8. Two schools followed with 7; the next had only 5. The top three schools were far ahead.

The contest itself was unnerving. Perhaps the problem setters had imitated the previous World Finals’ extreme difficulty. For the opening 20 minutes, the room was silent and nobody solved anything—abnormal even at the World Finals. Waterloo’s winning team recorded its first acceptance at 42 minutes; the runner-up and our team did not score until after an hour. The set began at medium difficulty, with no easy entry problem. Teams below 22nd solved only one, and those below 42nd solved none. For ordinary contestants, it must have been miserable.

No problem particularly stayed with me at the time. Only later did I revisit Problem I and appreciate how good it was: computational geometry preprocessing followed by network flow, genuinely World Finals caliber. We discarded it immediately. Waterloo solved it after the freeze, fully deserving the title.

We finished third and grew slightly nervous. Strictly speaking our region still had only two guaranteed places; third depended on a wildcard. Given these results, surely the wildcard would come to us.

It did, and we qualified without further drama.

We again entered NAIPC and placed sixth for a silver award. The prize was already incomparable to the previous year: a $150 Amazon gift card per person. Had the contest gone bankrupt after one edition?

We trained a great deal that year, hoping for a strong World Finals result.

2016

I did not participate the previous year because our student coach was still in place. In 2016, during the fifth year of his PhD, this exceptional competitor simply left the program to start a company.

I was astonished. From the Chinese perspective I knew, leaving in year five was almost incomprehensible. Graduation was close; why abandon that investment rather than endure a little longer?

Americans, however, often made such decisions more freely. He wanted to found a company, so he did.

Michigan was left with a vacuum. The faculty coaches generally did not manage student training; the student coach did. When he departed, I stepped in, feeling as though I had been summoned in an emergency.

I worried over every aspect of the program, beginning with recruitment. All three of us had retired the previous year, and Michigan’s regional results had predictably collapsed. Team Two did best in 12th, followed by Teams Three and Four, while Team One fell below 30th. So much for a qualifier that supposedly assigned teams strictly by rank.

Knowing the talent pool was empty, I recruited personally. That summer I assisted an introductory algorithms course and invited every high-finishing student to compete. They did not look strong enough to qualify, but they were better than nobody.

At the start of term I prepared practice contests, contacted the leading students one by one, and found a younger student from SJTU with contest experience. After considerable persuasion, he agreed to enter.

Eventually I found three contestants who had each earned first prizes at Chinese provincial competitions. That ought to have been enough for qualification.

Reality disagreed. Their weak implementation prevented them from qualifying—and they did not even survive our internal team selection intact.

They had consistently occupied the top three in practice, so I relaxed. Then the official qualifier produced another surprise.

Two American contestants who really were brothers—the older and younger brothers—finished first and third. Unlike our 2012 surprise arrivals, they had attended practice and performed reasonably, but never this well. Apparently they had chosen the right moment to peak.

My three recruits landed second, fourth, and fifth. Team formation became awkward. They naturally wanted to stay together, particularly because one spoke very poor English and pairing him with Americans would have made everyone uncomfortable.

I entered a prolonged argument with the faculty coach, who insisted that the top three form Team One. I urged him to consider the contestants’ preferences. After several rounds, he agreed if the two brothers consented.

They did. My impression was that they had no strong preference; merely placing this high was unexpected, and qualification for the World Finals probably had not entered their minds.

Ranks 1, 3, and 6 formed Team One; ranks 2, 4, and 5 formed Team Two.

The sixth-place contestant now entered the story. I called him the Hong Kong Correspondent. He was Chinese, studied in Hong Kong, and was at Michigan for a single exchange semester. He was not a journalist; the nickname reflected his extraordinary command of contest gossip. Ask him anything and he knew it, living up to the old joke about reporters who somehow reach every corner of the world before their Western counterparts.

After selection, he asked about training and essential algorithms. He had begun programming at university and competitive programming only that semester, so his foundation was thin. I did know one shortcut. After years in this regional, I knew its style: nearly every contest included network flow, and the flow problems had grown easier. I had even placed two in the internal qualifier specifically to identify contestants who could solve them.

I told him to ignore everything else and concentrate entirely on network flow.

That advice proved invaluable. Neither brother knew flow. The Correspondent solved the regional’s flow problem, giving the team enough solved problems to surge into second place in the final 10 minutes and qualify. Otherwise they likely would have finished outside the top ten.

At the time, however, I devoted more attention to Team Two. They were easier to summon informally and always came when asked; Team One generally appeared only for official practice.

The three recruits’ implementation ability stunned me. Once, nobody attended my office hour, so I brought them in to practice a basic single-source shortest-path problem. I came apart watching three provincial first-prize winners fail to code it in ninety minutes. Had I really been this weak in my first season?

They continued failing to debug easy practice problems. At the regional, weak coding again cost them straightforward problems, and Team One completely outclassed them.

The older American was an exceptional implementer, both fast and disciplined. According to the Correspondent, he followed OOP rigorously, defining classes rather than relying on loose functions and global variables. That was rare in contests because it increased code volume and usually reduced speed. Its benefit was equally clear: when something failed, his structured code was much easier to debug.

Team One qualified, and I was delighted: another World Finals trip. Then we learned it would be held in the United States, and I was disappointed.

The Correspondent returned to Hong Kong after the semester, and the team barely practiced together. I later heard they did some online training, but we all know how effective that tends to be. At SJTU, we too had claimed to practice online.

Everyone else remained. Their algorithmic foundations were so weak—or nonexistent—that I began an informal class.

It was entirely volunteer work. I mainly wanted the two brothers to learn the standard algorithms before appearing at the World Finals.

Then another contestant came into focus: a different American whom I will call American Two. He had finished seventh in the qualifier, led Team Three, and was clearly dissatisfied with that outcome.

The brothers attended perhaps 60 percent of the class. American Two came every time. I taught extremely quickly because time was short and the syllabus broad; within three or four weeks attendance had nearly vanished. Once, he was the only person there, and I delivered the entire session to an audience of one.

Over the semester I felt I had passed everything I knew to him. How much he absorbed remained unclear.

2017

Another season arrived.

I again recruited everywhere, though I now had some confidence in the American contestants, particularly after American Two had learned many algorithms and the older American had reportedly become even faster.

At the information session I met two Peking University graduates beginning graduate study at Michigan. Unlike the previous year’s three recruits, both had competed on Peking University’s ICPC teams—perhaps not Team One, but Teams Two, Three, or Four. They possessed genuine ICPC experience and should at least have reliable implementation. I was excited. I probably could not have made SJTU’s fourth team; surely someone from Peking’s second could handle a regional without my help.

So I gave them none.

Both underperformed in team selection. I thought the contest itself was excellent: every problem was solved by at least two people, nobody solved all 12, and the winner finished with 9—the most balanced outcome I could imagine.

My one regret was a mathematics problem whose derivation seemed wonderfully elegant. In practice, contestants either knew the result and solved it immediately or had no avenue to derive it during the contest. That was poor design.

With enough problems and separation, the qualifier remained dramatic to the end. I invited my former mathematics teammate to watch online. The final 30 minutes brought repeated reversals: American Two used his solid algorithms to reach first with 9 at 15 minutes remaining; then, with four minutes left, the older American found the mathematical result and jumped to second with 8. Until then we had blamed that problem for potentially excluding him from Team One. He rescued himself on merit.

The top three became the older American, American Two, and an unfamiliar American I will call American Three. The two Peking graduates finished fourth and fifth, hurt chiefly by penalty time and perhaps by my mathematics problem. The Americans seemed to know the result; neither Peking contestant did. Without it, both might have reached Team One.

I liked the resulting structure. With the older American and American Two anchoring Team One, regional-level strength was secure; who the newcomer was scarcely mattered. The two Peking contestants made Team Two so strong that, as a joke, its third member almost seemed optional. The top five were far ahead: fifth solved 8, sixth only 5.

At the regional, Team One justified that confidence. The older American was extraordinary. Others read the problems, but he wrote every solution, coding 6 accepted problems in 1 hour 14 minutes and taking the lead. Progress slowed afterward, but they added two more and qualified as the region’s second-ranked school.

Team Two matched their solved count with more penalty. Without Team One, their third-place school position would probably also have qualified.

Nothing more was needed that year. Both Peking contestants planned to return, so the next season looked secure.

Then I learned the World Finals would be in China. So much for free international travel; I would treat it as a university-funded trip home.

2018

Another season began.

Both Peking contestants returned. We seriously discussed whether they were still eligible. People generally believed students more than five years into university could not compete. Reading the rules closely, however, we understood the two conditions to be alternatives: either the enrollment-year requirement or the birth-date requirement might establish eligibility. That was our understanding at the time.

While serving as a teaching assistant for algorithms, I recruited one more contestant: a fellow SJTU alumnus who was now a PhD student, with contest experience but none in ICPC. That seemed fine. The Peking pair could implement; he could concentrate on analysis. After considerable persuasion, I had another all-Chinese trio. The World Finals location was already known to be Portugal, so the four of us created a chat called the “Portugal Tour Group.” Results there hardly mattered; qualification was enough to secure the trip.

Team selection ruined the plan. The first Peking contestant, the SJTU contestant, and the second Peking contestant solved 8, 5, and 4, placing first, third, and fifth. Pulling fifth into Team One would be difficult. Second place belonged to American Three, with 6. In short, first was far ahead and everyone else occupied supporting roles.

The fifth-place contestant had only himself to blame. A little over an hour in, he attacked the hardest problem and remained stuck until the end, at one point questioning the data. When I explained the solution afterward, he realized his approach was wrong. Who plays a contest like that?

The second Peking contestant withdrew from consideration. The first Peking contestant, the SJTU contestant, and American Three formed Team One. Our Portugal Tour Group officially disbanded.

With reasonable execution, this team could still have reached the Finals. Instead, at the regional, they again failed to implement easy problems. They did finish as the region’s third-ranked school, but first solved 9, second 8, and they solved 5; no wildcard was awarded.

It was frustrating because their only opponent seemed to be themselves. They were going to finish third regardless; a marginally better performance might have secured the wildcard.

The Portugal Tour Group was formally dissolved.

My coaching career ended there. Across six visits to the same regional site, I qualified twice as a contestant and coached two more qualifying teams. It had, on balance, been a distinguished run.

I did not yet know that an entirely new chapter of the World Finals was about to begin for me.

This was my first ICPC World Finals, and I was tremendously excited. At the time, it was still called the ACM-ICPC World Finals.

I will skip the path through regional competition here. For us, that road seemed to lead through Grand Rapids, Michigan, every year. For the full story, see the regional-contest collection.

I do have to say something about the Russian visa, because it was among the most difficult I have encountered. The application required the original invitation issued by the event. First, the organizers had to be authorized to issue such a document at all; then the physical original had to survive international shipping. It looked appropriately formidable: special brownish-yellow paper covered in text I could not read, with a serial number, my name, signatures, and stamps. That document then had to cross an ocean from Russia to the United States. If it had disappeared in transit, I suspect the practical answer would have been to give up. We eventually hired a travel agency to handle the visa and book the tickets. As far as I remember, the visa alone cost each of us more than $300. Fortunately, the university reimbursed it.

Before the contest, I was in China while both teammates were in the United States, so we had almost no team practice. We attempted two online sessions, coding while connected by video call. They were essentially useless. Before I returned to China, our academic schedules had allowed only a handful of practices together; otherwise, everyone trained alone. We were walking into the World Finals with almost no team preparation.

The trip itself began with a request for leave. I never imagined that I would need formal permission to miss time at a university, much less that obtaining it could become this complicated.

I was enrolled in the 2+2 program at the University of Michigan–Shanghai Jiao Tong University Joint Institute. I spent the first two years at SJTU and the next two at Michigan, then returned to Shanghai for a final-semester capstone project. Completing it meant receiving degrees from both universities. Students could choose not to return, in which case they would receive only the Michigan degree. In practice, many people who planned to work in the United States stayed there instead. From that perspective, returning to Shanghai for the second degree seemed less useful than spending the semester on another U.S. internship, which was far more likely to help with recruiting. The result was an unusually low completion rate for the dual-degree path. As far as I remember—and my memory may be off—it was under 80 percent, probably near the bottom at SJTU.

I was now back at SJTU for that final capstone semester. I already had enough credits, so the project was my only course. I had returned largely because I still did not know where I wanted to build my career and thought it prudent to secure both degrees first, even though I would most likely work in the United States. That made me remarkably relaxed about the consequences. If I somehow failed to graduate from SJTU, I could live with it; I would simply have spent a summer in China with friends.

That was the background. Then contest week approached. University students skip class all the time; this is hardly unique to China, and professors at Michigan rarely took attendance either. What surprised me was that, in an environment where quietly missing class was routine, formally asking permission to miss it seemed almost unforgivable.

I had not planned to request leave at all. There were only two class meetings that week, and I could simply have skipped them. Unfortunately, the second capstone presentation fell in the same week and counted for 5 percent of the final grade. I was not concerned about losing those points; passing the course should not have been a problem. But when I spoke to the faculty member leading the capstone supervisors, he told me I could not miss it: failing to attend any presentation meant failing the entire capstone.

I was stunned. How could missing something worth 5 percent automatically mean failing the course? I searched the syllabus, grading documents, and every other piece of course information I could find. None mentioned such a rule. I might have understood it for the final defense, but this was only the second presentation, with two more still to come. I could not understand the decision. With the limited perspective I had then, I could only interpret it as my request having bruised his pride.

There was little I could say beyond explaining that this was an important competition—the World Finals—and asking whether formal university leave would make the absence acceptable. He said he might consider it if the leave were official. So I had no choice but to begin the process.

That meant going to my student advisor. I no longer remember how many signatures were ultimately required—perhaps three—but his approval came first. I explained that I needed leave for the competition. His manner was gentler than the faculty supervisor’s, but the underlying questions were similar: Why did I need to go? Was the capstone not important? Did I truly have to attend? My answer was firm: yes, I had to go. As I said above, I privately placed little value on the SJTU degree if I ended up working in the United States and was prepared to do without it. I did not say that aloud, of course, but it made my outward position very clear. I was going.

Perhaps my advisor was persuaded by that resolve, and perhaps by my earlier record at SJTU: I had ranked second in the institute by GPA and received an academic achievement award, so I had a well-established reputation as a good student. He finally approved the leave and told me to compete well and bring honor to the university.

The awkward part was that I was representing the University of Michigan. SJTU’s programming team was already exceptionally strong; it certainly did not need me, and I doubt I could have made that team anyway. Naturally, I said none of this. I still wonder what my advisor would have thought if he had known I was not competing for SJTU at all.

Eventually I obtained the leave and the necessary senior signatures. I returned to the faculty supervisor, who agreed to deduct the 5 percent without failing me outright.

It had taken an absurd amount of effort. As an introvert, I felt as though this one request had consumed my entire social quota for the year.

At last, with nothing left hanging over me, I could go compete.

I flew alone from Shanghai. My teammates and coach traveled from the United States. As noted earlier, many students chose to remain in America for internships rather than return to SJTU for graduation, and one teammate had done exactly that. His standard U.S. technology-company summer internship lasted twelve weeks—exactly twelve weeks—and he needed to miss an entire one of them. That could not have been easy either. His account also included some version of “I absolutely have to take this week.” Somehow he cleared every obstacle and secured the time off, despite the risk that it might hurt his chances of a return offer.

My flight connected in Moscow, as flights to many parts of Russia seemed to do. The transfer was smooth until immigration. The officer asked where I was going. I said, “Yekaterinburg.” He replied, “Екатеринбург?” I repeated, “Yekaterinburg.” He repeated, “Екатеринбург?” And around we went.

That is almost a transcript of what happened. I was speaking English, and he mostly was too, except that he pronounced the city in Russian. The Russian and English pronunciations differ substantially, especially in where the stress falls, and I had no idea what he was saying.

Eventually he seemed to understand me and let me through.

I reached Yekaterinburg, arrived at the hotel, and met my teammates. Then all three of us realized the same thing: nobody had brought a plug adapter.

It was not our first time abroad—we had all obviously been to the United States—but that had been different because we lived there long enough that buying adapters was unavoidable. This was probably the first trip for all three of us to a country where an adapter was genuinely necessary, and not one of us had thought to pack one.

We appointed a representative to ask the front desk whether we could borrow one. That representative was me. My English was not very good then. After I tried socket, power, and charger, the receptionist smiled and said, “I think what you want is an adapter.” To be honest, I did not know the word, but it sounded convincingly like the object I needed.

I obtained one adapter. For the rest of the week, all three team members gathered in one room every day and took turns charging our devices.

I barely remember what we did during those days. I think our coach took us to a few sights around the city, but I cannot recall what any of them were. Nobody on the team spoke Russian. Our assistant coach, as I remember it, may originally have been Russian but had moved to the United States for reasons he did not really spell out. According to him, if he entered Russia again, he might have great difficulty leaving. He phrased it carefully, and that was only how I understood it. Had he been with us, perhaps we would have seen more of the city.

Then contest day finally arrived. The problem set was catastrophically difficult. A rumor circulated that the Judges—the people who selected and prepared the problems—had deliberately made it brutal because they feared tourist might finish early by solving the entire set before the five hours were over. Gennady Korotkevich, known by the handle tourist, was widely regarded as the strongest competitive programmer in the world at the time. His team had come very close to finishing the previous year’s set. According to the official post-contest analysis, three extreme test cases had been added to the hardest problem shortly before the contest; without them, his team would have solved the entire 2013 problem set.

Whatever the origin of the rumor, and whatever caused the difficulty, the 2014 set was a disaster. Years later, after I became a World Finals Judge myself and learned how problems were selected, I found that year even harder to explain. I asked a number of people who had been involved, and their answers were variations of, “Was there something unusual about that year? I don’t remember.” The rumor was probably nonsense. To the Judges, it appears to have been an ordinary World Finals whose difficulty simply went badly off course.

Back to the contest.

The first solve on Problem K came at 17 minutes. By the 15-minute mark, we already knew something was wrong. In a normal year, the first solve would almost certainly have appeared around ten minutes; this time the entire scoreboard was still silent. Things did not improve after K was solved. Usually, once the first problem falls, every team turns to it and dozens have accepted it within an hour. Here, almost nobody followed. We read K, had no idea how to solve it, and fell quiet ourselves. We could tell it was a data-structure problem but could not see how to use one. We submitted a few improvised optimizations, accumulated eight wrong attempts, and never solved it. The solution required a range minimum query structure. At the time, we were nowhere near good enough: all three of us had heard of RMQ, but none had mastered even that basic technique well enough to recognize it.

The deadlock lasted until minute 28, when someone solved D. We reread it and decided it might be manageable. Earlier we had not been sure; it was not an obvious easy problem. But if another team had solved it, then it had to be possible. One teammate took it on, and roughly an hour later we accepted D, our first solve of the contest.

Problem C received its first solve at minute 35. It was computational geometry: clearly solvable at first glance, but full of cases and difficult to get accepted. All three of us were weak at geometry, and whenever one appeared, I was usually the person sent in to improvise. As expected, C had case after case. We made six submissions and never solved it. During the contest, we thought we were close. Afterward, we downloaded our code and the official data and discovered that we were nowhere near the correct solution. The computation used real numbers but required integer output, demanding careful treatment of precision. When a result lay arbitrarily close to an integer, different cases required rounding up, rounding down, or taking the nearest value. Three computational-geometry novices were not equipped for that distinction. We had no realistic chance of getting C accepted.

At minute 68, someone solved I. We read it and could not solve it either—but this time our reaction was different. We looked at the team with the first solve and thought, Wait, that team solved I? Then surely there had to be some way to hack it. We still could not devise a clever heuristic, so we used the bluntest possible approach: brute-force search with deliberate time management. The program searched until it was close to the time limit, stopped, and printed the best answer it had found, whatever that happened to be. It worked. As a precaution, we randomized the input order first in case the data had been designed to punish a fixed ordering. Our first four submissions failed because the stopping threshold was wrong and the program exited too early. After tuning the parameters, our fifth submission was accepted. The team with the first solve on I did indeed finish the contest with only that one problem. That has to be one of the strangest one-problem performances in World Finals history.

The other solved problems had little to do with us. We would read one, realize we had no idea how to solve it, and quietly move on.

We recognized B as a knapsack dynamic program requiring the multiple-knapsack optimization, but nobody remembered how that optimization worked. In fact, the problem required taking the underlying idea and deriving an additional optimized formula. We were plainly not capable of doing that on site.

E was the most painful missed opportunity. We read it and found no direction at all. In reality, its entire logic matched DFA minimization, which one teammate and I had studied together only a year and a half earlier. Somehow neither of us remembered it. The problem should have been a gift, but in the contest we never saw the connection.

We also attempted A. Nobody solved it during the contest, including the unofficial teams. We tried largely because we could not do much else. It was a constructive, ad hoc problem rather than an algorithmic one, so one teammate spent three hours thinking about it from the middle of the contest onward. He submitted twice without success. Afterward, our coach asked whether those submissions had been serious. They had. A was in fact solvable, but the empty column on the scoreboard had frightened every team away. Someone later asked the Judges, who had apparently regarded it as the easiest problem in the set—something they expected to be the first solve and then widely accepted. That mismatch was remarkable. For the four cases of n mod 4, the true optimum was n in every case. My teammate had successfully derived n for three of them; for the last, he could only reach n+1. We had come painfully close to what might have been the first—and perhaps only—official solve of A.

We finished the contest with two problems solved.

The frustration afterward was palpable. A World Finals set this difficult felt almost unheard of, which helped the rumor about stopping tourist from finishing early spread quickly. An unofficial tourist team solved seven problems with a lower penalty time and would have placed first, but unofficial teams did not count in the standings. They nearly reached eight or more. One member spent an hour on A and still did not solve it, further evidence that it was not remotely trivial. J was ingenious: its broad direction was visible, but the derivation was punishing and the implementation enormous. Petr later described a moment in which the coding was finished, only for the team to realize they had forgotten the requirement for the lexicographically smallest answer—and abandon the attempt.

The Resolver then produced a dramatic reversal. At the scoreboard freeze, Moscow State University led with six solved problems while second place had only four. Given the difficulty, the championship looked all but certain. Instead, St. Petersburg State University solved three problems in the final hour, also finishing with seven and winning by 39 penalty minutes. Their last accepted submission came after eight wrong attempts, with only two minutes left in the contest. It could hardly have been closer.

Those stories aside, all three of us were deeply disappointed. We agreed on one thing: we would return the following year.

After our dismal performance the previous year, we decided to prepare properly this time.

The division of labor among the three of us was now quite clear. I handled implementation-heavy problems and the more exotic algorithms, so over the year I learned a great many techniques I had never even heard of before—half-plane intersection and the Aho–Corasick automaton, for example. Their names sounded suitably elaborate, but they were also genuinely useful. My own training method was to work through problems from previous regional contests, which covered most of the standard algorithms reasonably well.

My mathematics teammate handled mathematics, dynamic programming, greedy algorithms, and anything else with even a hint of math. He trained by competing on Codeforces and Topcoder. Their problems differed substantially from the ICPC style: almost every problem involved mathematics to some degree, and the shorter contest format limited how much code a solution could require. That made them well suited to learning this side of competitive programming.

My problem-reading teammate, who did not code at all, was responsible for knowing all the strange things. Our expectation was simple: he did not need to implement them, but he needed broad exposure to everything. His training method was to open an online judge and read the problems in order. If he could not solve one, he read the editorial. Whenever he encountered an unusual technique, he remembered it and told us if it seemed like something the rest of the team ought to know.

Beyond individual practice, we trained together vastly more than the year before. To prepare for the contest, all three of us took the minimum course load in our final semester—and easy courses at that—so we could devote more time to training. My mathematics teammate and I were first-year graduate students; our problem-reading teammate was a senior. We began at roughly one team contest per week, increased to two near the end of the semester, and practiced every day once vacation began. A contest alone lasted five hours. Add the time needed afterward to finish every problem we believed we should have solved, and the entire day was gone, sometimes with work still left.

As the training accumulated, so did our confidence. We ran five-hour virtual contests on Codeforces and noticed that many teams heading to that year’s World Finals were practicing the same sets, though virtual participation meant we did not start at the same time. We encountered teams from Tsinghua, Peking University, Shanghai Jiao Tong, and several European universities. The more contests everyone played, the more often even excellent teams had an off day. In other words, we eventually managed to beat nearly every strong team we could find at least once. Our conclusion was irresistible: if our luck and form were good enough, was there any team we simply could not beat? After some thought, only tourist’s team came to mind. Our goal for the year was a medal.

The contest eventually demonstrated that “if our luck and form were good enough” was a rather demanding condition. On the day, our performance was merely normal, perhaps slightly below normal.

There was a more serious problem. Most of the virtual contests we practiced on Codeforces came from Russian training camps. Russia had exceptionally strong teams—ITMO University in St. Petersburg, tourist’s school, had already dominated the championship for years—but those camp problems differed markedly from the World Finals. Their style was closer to Codeforces itself: heavy on mathematics and light on implementation. Put simply, those contests may have trained my teammate very well while doing almost nothing for my own ability to implement pure coding problems. Unfortunately, I did not recognize this until our post-contest review.

That year the three contestants, our coach, and the assistant coach who had been unable to travel to Russia the year before all flew to Morocco together. I remember almost nothing about the organized sightseeing in the days before the contest. My mind was probably occupied entirely by the competition.

What I do remember is the heat. Going outside felt unbearable; all I wanted was to stay in an air-conditioned room. A friendly man on the street noticed how hot I was and began talking to me about the weather. I understood none of what followed until he pointed into the distance and declared, “the great Sahara!” That part I understood. I assume he was proudly reminding me that the Sahara was nearby.

One incident remains especially vivid. Our assistant coach, who was of Russian background, could be remarkably fearless. In a market in central Marrakesh, we came across a tattoo artist working from a street stall. Do not ask why a tattoo artist had a street stall. It looked unreliable at first glance and not much more convincing at second. Our assistant coach suddenly decided that perhaps he should have a tiger tattooed on his arm. The artist asked him to draw the design, so he sketched what looked like a cartoon cat on his arm.

All three of us had exactly the same thought: if you go through with this, do you still want that arm? In the end, for reasons I do not remember, he did not get the tattoo. Perhaps he eventually decided that the operation looked as dubious as we thought it did.

The market also had vendors selling freshly squeezed orange juice. The press looked extraordinarily wasteful. An orange was cut in half, one hemisphere was placed peel-side down in the machine, and a lever crushed it. The juice came out; the half orange was finished. Even by sight, the yield looked terrible. Still, the juice was excellent. Perhaps the waste was the reason: none of the peel, or even the membrane around the flesh, made it into the drink. There was no bitterness at all, only sweetness.

I had never seen a machine like it. Several years later, on a trip back to China, I encountered the same technique at an airport in a fully automated vending machine. You paid, and it cut three oranges in half and pressed them on the spot. The machine was evidently not very precise. It jammed midway through, stole one of my oranges, and left me with a cup only two-thirds full. There was, naturally, nobody to whom I could appeal. A few years after that, I never saw those machines again. Perhaps the ingredients were too expensive, the machines too unreliable, and the complaints too numerous for the business to survive.

Back to the contest. The three of us discussed running one final practice round on site, then abandoned the idea. It sounded unnecessarily painful, and we could not see what last-minute cramming would accomplish.

On contest day, we entered the hall and found balloons in thirteen colors. That meant thirteen problems, an unprecedented number. By all logic, one of them ought to be exceptionally easy—a free point. That was exactly what happened.

Someone solved A five minutes after the start. It was indeed the giveaway. We followed and accepted it at minute 11.

Then we looked for the next problem. B was geometry and appeared hopeless, so we discarded it immediately. F and M were implementation problems that did not seem conceptually difficult but would take time. D looked at first glance like a mathematical problem involving calculus. Our problem-reading teammate identified C as a straightforward network-flow problem. I checked it, agreed, and began coding.

At minutes 28, 29, and 30, teams solved F, C, and D in succession. That reinforced our belief that C was simple network flow. I finished the implementation at minute 35, submitted it, and received a wrong answer. Awkward. I read the code twice, found nothing, and we were stuck.

We asked our problem-reading teammate to debug C while I began implementing F and our mathematics teammate derived the formula for D. At around the one-hour mark, the debugger found a missing case in C. We added it, revised the code, and accepted the problem at minute 63.

I probably spent more than half an hour coding F, then another twenty minutes debugging it against the sample. My implementation skills were simply not good enough. I submitted at minute 93 and got a wrong answer. We printed the code and continued debugging offline.

Our mathematics teammate began coding D. He had written very little geometry before, so I warned him to use a sufficiently long constant for pi—I had been burned by that before—and to use long double, not double, anywhere performance did not matter. During that time I found the problem in F, took the computer briefly to fix it, and accepted F at minute 102.

D was accepted on the first attempt at minute 112.

We now had four problems. When we looked up at the scoreboard, the contest had transformed. L, J, and I had received first solves at minutes 39, 47, and 53; E and H followed at 115 and 118. Nine problems had now been solved by someone, while the leader—I remember it as the University of Tokyo—already had seven. Seven problems in two hours was unprecedented. According to an analysis we had previously heard from a Carnegie Mellon coach, when nine problems were solved within two hours, a medal would require ten and gold would require twelve.

Our mathematics teammate started on L while I coded I. I was a simple interval-merging problem: given several groups of segments, compute the total length covered by every group. Our first idea was a segment tree, specifically a coordinate-compressed one because the endpoints were real numbers. That seemed implausibly elaborate given how many teams had already solved the problem. Were they all implementing compressed segment trees? Then again, this was the World Finals; perhaps they were. We eventually learned that we had badly overthought it. If we represented every uncovered portion as a segment, the task became finding the length covered by at least one such segment. Subtract that from the full range, and one sort was enough.

Instead, we wrestled with the compressed segment tree. It was not an especially complicated data structure, but we had never implemented one in this form. Our first wrong submission came at minute 126. There were countless boundary cases and comparisons between real values waiting to go wrong, so a very long debugging session began. I consumed more time on I than on any other problem. We submitted roughly once every half hour, accumulated four wrong attempts, and finally accepted it at minute 269. From beginning to acceptance, I had probably spent more than three hours on what was supposed to be a simple problem.

While I debugged I on paper, our mathematics teammate implemented L. It was not particularly complicated, and he accepted it on the first try at minute 173.

Then there was J, the strangest problem of the contest. It looked mathematical. After reading it, our mathematics teammate asked whether either of us knew an algorithm for multiplying two very large integers quickly. We did not. The answer was the fast Fourier transform, FFT. None of our practice contests had included an FFT problem, so none of us knew it. Our teammate had identified exactly what was needed, lacking only an FFT implementation. What could we do? Submit a lookup table.

The input contained only one integer, which made the problem ideal for hardcoding precomputed checkpoints into the source. We estimated the size and realized that the table might actually fit. The required file size depended on the sampling interval. If we stored one value for every hundred numbers, we would submit a program of roughly 100 KB, but a query falling between stored values would require computing as many as one hundred additional cases at runtime. Storing every fiftieth value would produce a 200 KB program but halve that work. We did not know the maximum permitted source-file size, so we decided to stop worrying and try it.

That began our long battle with the table. It should not have been so difficult, except that the contest laptop was painfully slow. My teammate tried to save a 100 KB source file and the computer froze, nearly crashing. The cursor spun for a full thirty seconds before the save completed. Every save was terrifying because we expected the machine to die. We had to operate carefully; copying and pasting too much data at once might freeze it again. Saving frequently is normally a good programming habit. Here it became a liability. Whenever my teammate instinctively pressed the shortcut before he was finished, he would immediately swear and ask why his hand had betrayed him again.

The next two hours consisted mostly of me debugging the compressed segment tree while he debugged the enormous table. We took turns at the computer, took turns submitting, and took turns being wrong.

Before the scoreboard freeze, the minimum number of problems in medal position had already risen to eight. We were stuck on two and had no idea how to free ourselves. Since our goal was a medal, we had to open another problem. While the mathematics teammate and I were occupied, our problem-reading teammate started E and judged it solvable with a simple greedy algorithm. I quickly implemented that greedy idea and got two wrong answers. He could not tell whether the algorithm or the code was at fault. We were now stuck on three problems. Then the mathematics teammate glanced at it, said the greedy approach was obviously wrong, and produced a counterexample in thirty seconds. E became completely inaccessible, returning us to being stuck on only two.

Our final submission of the hardcoded J solution came four minutes before the contest ended. It was accepted, with considerable difficulty, and that concluded our contest.

The one distinction worth mentioning is that we solved J with a lookup table, and we were the only team in the contest to do so. The official post-contest analysis specifically noted that hardcoding was possible, and that one team in the field had actually used that approach. That team was us.

At the time, I wondered whether the problem setters had never considered hardcoding at all—whether our submission made them realize it was possible, prompting them to add that paragraph to the analysis. Ten years later, after becoming a Judge myself and learning both the people involved and the standards of problem preparation, I consider it overwhelmingly likely that the Judges knew from the beginning that a table would work and deliberately allowed it.

We finished with seven problems. Ignoring penalty time, we were tied for 28th. With penalties included, we placed exactly 50th—the lowest-ranked of all teams that solved seven.

Afterward, we told our coach that we had solved every easy problem and therefore completed the basic assignment. But I and J had consumed so much time that we had none left for anything else. If we had not overthought I, and if we had known FFT for J, each problem could have saved us at least an hour. With that time, M, a pure implementation problem, might have been within reach. Our mathematics teammate would also have had a strong chance on H, a purely mathematical problem.

Reality offers no such revisions, so we were left with a few regrets. Congratulations went to tourist’s ITMO team, which solved the entire set before time expired, won with a perfect score, and became the first—and remains the only—team ever to finish a World Finals early by solving every problem. The hall erupted during the Resolver. Evidently everyone wanted to witness history.

Each contestant may appear at the ICPC World Finals at most twice. With that, my career as an ICPC contestant officially ended.

I was disappointed by the choice of location for that year’s World Finals. I was no longer a contestant, so attending was mostly an opportunity to travel, watch the contest, and enjoy the events. Naturally, I wanted the Finals somewhere worth visiting; Phuket, Thailand, the previous year had been a fine choice. This year, though… everyone who had heard of Rapid City before, please raise a hand. If you had never visited Mount Rushmore yourself, would you have known it was here?

The university paid for the trip, which immediately put me in a good mood. My only regret was that I was doing research on campus that summer and could otherwise have been a teaching assistant for a large course, earning what seemed like serious money to me at the time. After I spoke with the professor, however, he explained that the course had only one TA and could not accommodate someone disappearing for an entire week. So he turned me down. I had to TA a smaller course instead and earned only half as much. Still, there was nothing to deliberate over. Going to the World Finals was obviously more important.

Our team that year consisted of three students I called the “American Brothers” and the “Hong Kong Correspondent.” For their path through the regional contest—and the origins of those nicknames—see the regional-contest collection.

For once, I could join the day trip without a contest occupying my thoughts. The organizers took us to Mount Rushmore, the best-known attraction in the area. I went around with the Hong Kong Correspondent, whose reporter’s eye proved worthy of the nickname: he immediately spotted tourist, alone. After a moment’s hesitation, he rushed over and asked for a photo, successfully catching his chance. The Hong Kong Correspondent had always been a devoted tourist fan, so this was an enormous win. The moment the picture was taken, tourist appeared to activate a video-game escape skill and vanished at speed, plainly unwilling to be caught for another round of photographs. I did not get one. An enormous loss on my part.

All I can offer here instead is the bare rock of Mount Rushmore. Looking at the photograph of myself from that year, it is hard to believe that, despite being so young, I was already that young.

Afterward, we visited the Crazy Horse Memorial. What can I say? It was certainly a sculpture. The story as I heard it was roughly this: after the four presidents had been carved, a Native American chief objected. “We have our own great heroes,” he supposedly said. “We will carve a monument larger than your Mount Rushmore.” The planned sculpture was 172 meters high and 195 meters wide, more than twice the size of the Leshan Giant Buddha; the horse’s head alone would rise over five meters higher than the presidents’ heads. If completed, it would be the world’s largest man-made sculpture. More than sixty years had passed since work began in 1948. The chief and his seven sons had been moving their mountain one piece at a time, yet only Crazy Horse’s face had been carved. As the story went, the people behind the project did not want U.S. government money and hoped to build their national hero’s monument independently, relying entirely on private donations. The funding was therefore limited.

As for the current state of completion… the photograph speaks for itself. The small sculpture in the foreground, outside the shop, shows the intended result. The mountain in the distance shows the actual progress. Was it even ten percent complete?

When contest day arrived, I had no pressure at all, and the contestants did not seem to feel much either. They understood their own level. A ranked finish at the World Finals would be enough; anything but an unranked Honorable Mention.

They ended up with an Honorable Mention after all. The three of them solved three problems by minute 63 and then spent the remaining four hours working without another accepted solution. ITMO, entirely unsurprisingly, won the championship again.

I had no responsibilities at the venue and did not know anyone there, so I wandered around. Eventually I found a small group from Shanghai Jiao Tong University watching the contest and spent a long time sitting behind them, listening to their problem discussions. I had expected five hours to feel long, but they passed remarkably quickly. Sometimes I would stare at the scoreboard even though nothing had changed, with no idea what I expected to see. Then I would look up and two hours had disappeared.

After the contest, the organizers took everyone to a nighttime “light show” projected against the mountain. The quotation marks are deliberate, because my immediate reaction was: you call this a light show? I could gather a hundred people in the hills with laser pointers and produce something similar. It was painfully meager. It was not only my perspective as someone accustomed to China’s fondness for large, extravagant light displays. Even our American coach seemed unable to take much more. He wore an expression that said more than words could, then left early. From the look of him, one might have thought the show had personally embarrassed the United States.

I was even more disappointed by the choice of host city that year. I had been a coach for two years, and the World Finals had sent me once to the United States and once to China. Why? As a travel destination, I would personally take Beijing over Rapid City by an enormous margin, but I had already visited Beijing more times than I could count. I had never even studied there, yet I felt as though I had ridden at least ten complete circuits of Subway Line 2.

I wanted to see somewhere else in the world.

Still, the university was paying. I could treat it as a free trip home.

The team had three members that year, all American. For convenience, I will call them American One, American Two, and American Three. Their qualification campaign had been remarkably smooth: American One had delivered an exceptional performance and carried much of the regional contest. For the full story, see the regional-contest collection.

American Two had attended my algorithms class consistently since the previous year and worked extremely hard. I had taught him everything I knew. That was not an infinite supply of knowledge, but in terms of algorithmic breadth, it covered the kinds of problems one might encounter around the World Finals silver-medal level. How much of it he had absorbed was now up to him.

American Three’s distinct role in this particular lineup was, well, rather limited. American One was much faster at implementation, so there was little chance that he would take the keyboard. American Two had a broader range of algorithmic knowledge. Between those two strengths, most of what American Three might otherwise have contributed was already covered.

The hotel provided by the organizers was extremely luxurious. Our room was on the thirty-fifth floor—if I remember correctly, the highest floor accessible to guests—and the view was excellent.

The organizers arranged an excursion to the Great Wall. I did not go. Guess why.

A small group from our university then organized its own visit to the Forbidden City. I did not join that either.

In truth, I probably should have gone with them, but I had plans that day, so I let them venture out on their own. I decided to trust in the English-language competence Beijing had accumulated since the era of “Beijing Welcomes You.” Before they left, I asked the assistant coach, “Do you have any money?” He said no. “Do you have WeChat?” He did, but he had not yet worked out whether the payment function would actually work. “And you’re still willing to leave the hotel?” I asked.

I gave them all the cash I had, a little over 500 yuan. That seemed as though it should cover a day out. At the very least, it ought to pay for the tickets. Beyond that, they were on their own.

Apart from those larger excursions, I took them to the food streets near Peking University. That was when the limitations of my English as a non-native speaker became painfully clear. The assistant coach wanted milk tea. I looked at an entirely Chinese storefront and its endless list of optional ingredients and realized I had no idea how to translate any of it. All I could offer was: “They’re sweet. Just pick one.”

On contest day, I was still quite relaxed.

Compared with the previous year, however, I was slightly more nervous. In 2017 I had essentially been there for the experience. This time I had modest expectations for the team, especially given American One’s extraordinary implementation speed and American Two’s solid command of algorithms.

The result justified some of that optimism. They solved four problems and were officially listed in a tie for 56th place. More than forty teams finished on four problems, but our team was near the front of that very large group. If all the four-problem teams had been separated by the usual ICPC penalty ordering, they would have been around 60th overall. That was better than my own result in my first World Finals.

Unfortunately, Peking University did not win the championship. As the host team, they were clearly very strong and had given it everything they had.

One final episode occurred as I was preparing to leave Beijing. I was standing in a subway station with my suitcase, waiting for someone, when a salesperson from an English-language training company approached and asked whether I wanted to study English. I looked remarkably young then—young enough to be a student. In fact, I still was one.

“I don’t want to study English,” I said. “Are you hiring teachers?”

He replied that their standards for teachers were extremely strict, then launched into a long explanation to which I paid little attention.

At the end, for reasons I never understood—perhaps simple politeness, perhaps one final attempt to salvage the sale—he asked where I lived.

“San Francisco,” I said.

He went silent. After roughly three seconds, he said, “Are you messing with me?” Then he walked away.

You were the one who came over and started the conversation.

That year I was interning at Facebook, now Meta. During my internship, our group held an annual off-site in the United Kingdom. My mentor asked almost as soon as I arrived whether I wanted to join. I said I would think about it.

The first priority of an internship is securing a full-time offer. The entire internship lasted only twelve weeks. If I spent one of them in Britain producing nothing—and please do not tell me the off-site counted, because full-time employees attended the meetings while interns could only wander around outside—I had no idea what that might do to my return offer.

There were four interns in our group: three Chinese and one American. My U.S. visa and that of one other Chinese intern were still valid; the third Chinese intern’s had expired. If he left the United States, he would have to apply for another U.S. visa before returning, with no telling how long that might take.

That left three of us who could realistically go. Would we? Everyone kept telling me they were staying behind: too much risk to the offer, too dangerous, and so forth. I never asked what the American intern was thinking, but he decided not to go either.

I had never said that I was definitely going. Then, two weeks before departure, my mentor asked again: Was I coming? Was I really sure I did not want to? I should just go; it would be fine. The entire group would be in Britain for the week anyway. Even if we interns stayed behind, the eight-hour time difference meant that we would receive little guidance and would spend the week working on our own. Faced with such an enthusiastic invitation, I thought: why not?

The larger reason was that, at the time, I regarded job interviews as almost trivial. I was a competitive programmer. The coding interviews that terrified other people felt like quick runs through easy problems to me, and I believed I could interview almost anywhere I wanted. Unless an interviewer introduced some truly unpredictable complication, I did not expect to fail. I therefore did not attach quite the same life-or-death importance to the return offer as the others did. I decided to go.

Then came the British visa. What I remember most clearly is how extraordinarily expensive it was. Without company reimbursement, it was not something one could pursue casually. As I recall, I applied for a five-year visa that cost a little over $800 after conversion. Because I did not begin until two weeks before departure, expedited processing added several hundred more. My recollection is that the total came to roughly $1,300. That was quite a price for a visa.

On the other hand, once the fees were paid and the documents were in order, the process itself went very smoothly. Only a week passed between submitting the application and the consulate mailing my passport back. I should have been able to catch my flight.

Then the real complication arrived. I was a PhD student researching parallel computing, but this was the first time I had experienced just how much trouble an asynchronous consistency problem could cause in my own life.

The tracking page said my passport would arrive that morning, so I stayed home all day. The package could appear in one of two places: at my door or in the apartment complex’s parcel lockers. I did not know which the courier would choose, but because the package contained my passport, I intended to retrieve it immediately.

At about 10:30 a.m., I refreshed the tracking page and watched the status change from “out for delivery” to “delivered,” with the location listed as my front door. I opened the door and found nothing outside. Perhaps, I thought, the courier had marked it delivered downstairs before bringing it up, or something similar. I decided to wait five minutes. Five minutes later, nothing had happened. I concluded that the package was lost.

I reported the missing package online. Its status changed to an exception, and there it remained.

That afternoon I went to the nearby courier office and explained the situation. An employee said he would check when the day’s undelivered packages returned. Six o’clock arrived, and nothing happened. He said he would contact the driver. By after seven, he still had not reached the driver, who had finished work for the day. At that point he began spinning an extraordinary tale. According to him, mine counted as a failed delivery. The package would return to a holding center, board a plane with other parcels, take a grand tour of the United States to the company’s East Coast hub, be sorted again with local shipments, fly all the way back west, and somehow arrive at my home the following morning.

Listen to that story. If every misdelivered package had to follow such a route, the courier company would have gone bankrupt by the next day.

I am not exaggerating. I remember him saying exactly this, complete with expansive gestures, as though it all made perfect sense. There ought to be limits even to improvised nonsense.

The only conclusion I reached was that no conclusion was available there. The man plainly knew nothing and was making up the rest. I could only return the next day. It was nearly eight when I finally made it home from the courier office, physically and mentally exhausted.

Early the next morning, I returned to the office. Nothing had changed. The online status still showed an exception, and no one knew what had happened. The employee could only say that he would try the driver again. He failed to reach the driver that morning, despite the fact that the driver was now working. I went to work. That afternoon I returned, and he tried once more. At long last he reached the driver, who said he had already delivered the package but could no longer change its online status. The tracking page, meanwhile, still displayed an exception.

With the driver’s confirmation in hand, I went home again. The space outside my door was as empty as before. Now what? Could the passport possibly be in the parcel lockers? I had never received the usual text message saying that a package was waiting there.

I went to the lockers, tapped my building card, and one compartment sprang open. My passport really was inside.

I was delighted. I finally had my passport, and it now seemed that I could make the flight. Only four days remained before departure.

Afterward, I reconstructed the incident carefully. My background in computer science—and parallel computing in particular—proved unexpectedly useful in analyzing it.

Based on what the driver had said, my best reconstruction was this. That morning, the driver arrived beside the parcel lockers with a large batch of packages. He had scanned mine while still in the truck, changing its status to delivered. His next task was to put each package into a locker, scan it again, and then scan the locker. Under normal circumstances, the system would update the status to show delivery to a locker, while the locker system would send the recipient a message telling them to collect it.

I happened to intervene between those steps by reporting the package missing, changing its status to undelivered—or, in the system’s terms, an exception. When the driver later tried to scan my package, the scan no longer worked. What else could he do? He put the package into a locker and scanned the locker, presumably trying to trigger the notification. That also failed because the preceding step had already failed: the locker system could no longer associate that compartment with my package. The sequence ended with the physical passport inside the locker, the delivery system showing an exception, and no notification reaching me.

As for the courier employee’s story about my package touring the United States, that was pure invention—groundless and gloriously absurd.

I later told my mentor what had happened. He also thought my reconstruction sounded entirely plausible. What other explanation was there?

With passport and visa safely in hand, I could finally go to Britain.

Before all this, I had booked the flight and hotel through Facebook’s internal travel site, with the company covering both. The system showed me an $8,000 allowance for my flight to Europe, enough for a round-trip business-class ticket. It was my first long-haul international flight in business class.

The hotel was equally extravagant. I simply chose the first option recommended by the internal site. It stood in central London, less than 200 meters from the office. The price was $8,700 for less than a week—more than $1,000 per night on average. The booking site explicitly advised choosing one of its recommendations; exceeding the expected rate with another hotel might complicate reimbursement. If the system was willing to recommend it, I was willing to book it. It became one of the most expensive hotels I have ever stayed in.

On the day of my flight, some fellow interns saw me off over a spicy hot pot meal. I should not have eaten that hot pot.

A business-class seat could lie flat, but that did not mean I arrived in Britain feeling well. By the time I landed, my head felt ready to explode; the migraine was severe. At the hotel, I discovered that my power plugs were, as expected, useless. My plan had been simple: the office was so close that I could collect an adapter there after arriving. I had not anticipated arriving with such a headache. Going without power was not an option, however, so I forced myself to walk to the office and retrieve an adapter from one of its vending machines.

Facebook’s London office was unlike the Bay Area headquarters. It was not a campus but a single building spread across many floors. This was the lobby. A sponsor’s logo must always be enormous.

I collected the adapter and fled. My head hurt too much to remain.

By the following day, the pain had become so severe that I could barely get out of bed. At the time, I did not understand the cause and assumed it was merely the result of an eight-hour time difference. Only later, after taking more international flights and accumulating considerably more experience with jet lag, did I notice a pattern. I became fairly convinced that the hot pot had probably triggered it.

That afternoon, once the pain became tolerable, my determination to sightsee took over. I got out of bed and went in search of landmarks.

Our first stop was 221B Baker Street, Sherlock Holmes’s famous address. The uniformed man standing outside was in great demand; visitor after visitor wanted a photograph with him.

There was a long line at the entrance, though I had chosen a sensible time and it was not excessively long. Inside was a remarkably rich collection of rooms and scenes recreated from the stories, along with wax figures. The British clearly had their own deep affection for Sherlock Holmes.

We then visited Madame Tussauds London. This was the British Madame Tussauds—the place I had last encountered in an English textbook.

Next came Platform 9¾ at King’s Cross Station. It is not on a real platform at all, but beside a wall in the station’s public concourse, set up specifically for photographs.

The line was extremely long and moved painfully slowly. Staff dressed each visitor in a wizard’s robe, handed them a wand, and lifted the robe behind them so that it looked as though they were running, while someone captured the pose. The process took time. Between visitors, I photographed the empty setup and promptly escaped.

That ended the day’s itinerary. Every attraction had been within walking distance. Before my head could explode again, I hurried back to the hotel.

Over the next few days, I quietly completed some work at the office and met the remote mentor based there.

The World Cup was underway, and I watched a match on the enormous screen in the office cafeteria. This was a tradition dating back to the Facebook days: the Bay Area headquarters showed World Cup matches on its cafeteria screens all day as well.

Then the weekend returned. At last, my head no longer hurt.

Once I was up, my first destination was the British Museum.

The collection was certainly extensive. I paid particular attention to this internet-famous little figure apparently being slapped in the face.

We then went to the National Gallery. To be honest, I have little interest in art appreciation and even less ability. Yet several paintings there genuinely impressed me. Perhaps they were simply executed with such precision that they appealed to the scientific part of my brain.

That concluded the day. The museums were large, and I had spent several hours inside them.

The following day, I met a high school classmate who was pursuing a PhD in London, and he took me farther afield.

First came Big Ben.

It is too famous to require much introduction. At the time it was under restoration, wrapped in layer upon layer of scaffolding until it looked like a building being upgraded in a video game. Perhaps to spare tourists’ feelings, they had at least left the clock face visible. Ordinary construction scaffolding rarely seemed quite so carefully arranged.

Then came the Palace of Westminster, another building that appeared to have stepped directly out of my English textbooks.

Westminster Cathedral.

Buckingham Palace.

The London Eye.

Views over the Thames and central London from the London Eye.

Our final stop was Tower Bridge.

The commemorative photograph turned out exceptionally well.

That finally ended the day.

That evening, I said I wanted to try fish and chips. I had been in Britain for several days without eating its most famous national dish. My classmate took me from one restaurant to another, but none of them served it. At the last one, a member of staff gave us a distinctly disdainful look and suggested that we try a little takeaway place. His expression seemed to say, “What respectable restaurant would serve that stuff?”

Eventually, we really did find fish and chips at a small no-frills place—though it was technically a restaurant with a storefront. It was certainly authentic. And absolutely terrible!

To finish, here is the food from the flight home. This was only my second time in business class—the outbound flight had been the first—and in my unworldly excitement, I photographed everything that arrived.

And with that, my London journey came to a satisfying close.

Surprised to find me still here? Frankly, so was I.

I could already have graduated the previous year, and by now I was no longer even at the university. But the problem was much the same as in 2016: once I left, the student-coach position was suddenly vacant. The red-rated star stepped in, but a few issues involving our systems still drew me back. Michigan had its own judging system, built years earlier by my former student coach—an impressive achievement in itself. We had used it for years. It was basic, but remarkably complete.

I did not contribute much that year. I barely knew who the contestants were and did not attend the regional in person. What made the year different was the arrival of the North America Championship, or NAC. Previously, teams had qualified for the World Finals directly through the regional contests. Beginning that year, NAC added an intermediate stage. Each regional sent several of its leading teams; in ours, I believe it was roughly the top five.

This was the first NAC. As I remember it, regional contests still retained a direct qualification place at the time: the champion advanced automatically, while the remaining places were decided through NAC. A few years later, the regionals no longer had direct places and every team had to qualify through NAC. There was even a later occasion when a central region that had once sent four teams—allocations at the time depended on participation and other factors—saw every one of its teams eliminated at NAC, with none reaching the World Finals. In the years after the NAC system began, our region reliably sent three teams, sometimes more. It became rather easy to see which regions had not been quite as competitive as they thought.

The top five from our regional could reach NAC. That sounded almost too easy. There was hardly any pressure at all.

And indeed, the team qualified without difficulty. I followed Michigan to the inaugural NAC. I shared a room with one of the contestants, so my lodging cost nothing. I do not know whether there was an entry fee; whatever expenses existed, the university paid them. I did pay for my own flights, however. Officially, I was no longer at the university.

The overall schedule resembled the World Finals and lasted nearly a week. I had just started working, did not have that much leave, and had little involvement with the contest anyway. So I arrived midway through the event.

Under normal circumstances, someone would meet arrivals at the airport during the official arrival window. I apparently arrived too late. There was nobody at the airport and nobody at the metro station. I took the train to the contest venue by myself.

This was the hotel provided for the contest.

It was rather striking.

Contest day soon arrived. The competition hall was vast and open.

My impression was that NAC did not have many teams—perhaps a little over fifty—so it did not really need a venue this large. The organizers appeared to have arranged the room in a way that made the space look fully occupied.

During the contest, I spent most of my time discussing the problems with Michigan’s student coach, the red-rated star. It felt much like every other contest. Five hours looks long on paper, but at the venue it disappears remarkably quickly.

As for the result—well, never mind. I was not even entirely sure who was on the team. The only contestant with whom I had much connection was American Three, who was apparently still there.

We did not qualify, which was more or less what I expected. If reaching the World Finals had been that easy, what exactly had I spent all those earlier years doing as a coach?

Looking back much later, however, there was little to regret. The World Finals associated with that season was subsequently delayed substantially by the pandemic. Even if Michigan had qualified, I probably could not have attended because of my U.S. visa. The circumstances were very similar to the Bangladesh year; the full story is in the Egypt World Finals entry.

After many years away, I finally set foot at the World Finals again. I was thrilled, but also more than a little reflective—the eager heart was still there, though the hands were perhaps less steady. Time is unforgiving. Twelve years had passed since my first World Finals, and seventeen since I first encountered programming.

This was not, strictly speaking, my first time working as a World Finals judge. I had also been a judge for the contest in Bangladesh the previous year—or two years earlier, depending on whether one uses the event year or the calendar. I simply had not gone in person. Given how excited I was, I certainly would have gone if I could. The obstacle was not entering Bangladesh, but returning to the United States. For people like me who were living in the United States on a visa, international travel could make the US visa far more troublesome than the visa for the destination, especially for Chinese citizens. I faced the same problem that one of my fellow interns had encountered when I went to London in 2018: if I left the United States, I had no valid visa with which to return.

The pandemic made matters worse. China had not yet fully reopened, and returning meant an uncertain period of quarantine. US work-visa applications were also frequently being sent for administrative processing. Even if everything went smoothly, a trip home could easily keep me out for at least a month. Add the contest itself, and I would have needed roughly six weeks away—hardly a practical amount of leave for someone with a full-time job.

Another possibility was to apply for a US visa in a nearby country, such as Canada or Mexico. What I found online at the time suggested that appointments in Canada were already being scheduled a year out, perhaps because so many people had arrived at the same idea. Mexico appeared to be about six months out, though people said that an appointment within three months—or even sooner—might occasionally appear if one was lucky. There was no way to know until after entering the booking system.

I decided to try my luck. Unfortunately, this particular lottery had an admission fee. First I had to complete all the forms; more importantly, I had to pay before I could even see the appointment calendar. Payment itself was awkward and appeared to require someone local, which seemed like an excellent opportunity to lose money to a stranger. I found someone online who claimed to specialize in making these payments and asked him to handle it. The payment went through quickly. At least that part was not a scam.

The appointment calendar, however, was hopeless. I checked every US consular post in Mexico that offered visa services. Not all of them would handle cases like mine; some served Mexican nationals but did not offer the relevant interviews to third-country applicants. Every location I could use was booked more than six months ahead, far too late for the contest.

I refreshed the page quietly for two weeks and made no progress. It seemed that the only realistic option was to pay a professional appointment hunter to run a tool around the clock and hope it caught a cancellation. At that point I gave up. I treated the application fee as a donation to the US embassy.

There was another status-related complication. My US green-card priority date was close to becoming current under Chart B, while Chart A was still roughly a year away. For readers fortunate enough not to know this system: a green-card application begins with a PD, or priority date. In simplified terms, Chart A determines when an immigrant visa number is available and the case can receive final approval; Chart B determines when an applicant may be allowed to file early. Whether Chart B can actually be used in a given month depends on whether USCIS designates Chart A or Chart B for filing. Chart B generally runs ahead of Chart A, sometimes by a considerable margin. Because it governs filing rather than final approval, it does not predict when the green card will arrive. The dates can also retrogress: a chart may jump forward, attract a wave of applications, and then stall or move backward.

The obvious question is what good Chart B does if Chart A is not current and the card cannot yet be approved. In theory, that is true. In practice, green-card processing takes a long time. I hear it is much faster now, but in our day it was entirely ordinary to wait a year or more between filing and receiving the card. Earlier periods had been slower still, and an unlucky case caught in a sluggish process could take two years.

An unavailable immigrant visa number prevents final approval when Chart A is not current, but it does not necessarily prevent every earlier stage of processing. If USCIS permits Chart B that month and one’s date is current under it, the application can be filed and USCIS can begin its work. Once most of that work is complete, the case may wait for Chart A. If the priority date later becomes current and all other requirements have been satisfied, approval may follow relatively quickly. That can be vastly faster than waiting for Chart A before filing at all. In my customary shorthand: file two days late, wait two years longer.

In my own case, Chart B was on the verge of reaching my priority date. If USCIS allowed Chart B and I otherwise qualified, I could have filed. Leaving the United States during that window might have interfered with filing at the time, forcing me to wait until I returned—the details become even more complicated, so I will spare everyone. If Chart B then retrogressed before I came back, I would have regretted the trip for a very long time.

After weighing all of this, I decided not to attend the 2022 event—the 2021 World Finals—in person. It was my first year preparing and reviewing problems for the World Finals, and the experience was intimidating. A submission had to include a solution, but when a problem was assigned to me, no solution was provided. I had to work everything out and only then compare answers blindly with the original author. If assignments were random, this effectively required every judge to be capable of solving every problem, which was quite a standard. Fortunately, I had spent the previous two years improving and had reached red on Codeforces; otherwise, I doubt I could have done it. Secrecy was exceptionally strict. Every email and file had to be encrypted, as though interception were always imminent. Sending an email felt like participating in an espionage drama.

I later drew a diagram for one of my problems. It was spectacularly ugly, but nobody seemed inclined to replace it as long as the resolution was adequate. I also tried to hide an Easter egg in another problem’s test data by drawing the seven elemental symbols from Genshin Impact. The data was eventually removed for being unnecessary, after someone mistook the symbols for Pokémon types.

Then came 2023. The contest was originally scheduled for November in Sharm El Sheikh—yes, it was not supposed to be in Luxor at all. Then came the events everyone knew about. After the Israel–Hamas war began on October 7, 2023, security conditions across the Middle East deteriorated rapidly. Sharm El Sheikh was not close to Gaza, but travel, safety, and flight arrangements for many participants were affected, and the November plan was ultimately cancelled. The date became “to be determined.”

It was not until January 19, 2024, that ICPC sent participants a new message confirming April 14–19, 2024. The email first described the new venue only as “a famous city on the Nile”; Luxor was confirmed later.

The organizers had developed an unfortunate talent for choosing Egyptian venues just before trouble arrived. The 2011 World Finals had originally been planned for Sharm El Sheikh from February 28 to March 4. About a month before the contest, on January 25, large anti-government demonstrations began in Egypt as part of what became known as the Egyptian Revolution and the wider Arab Spring. Cairo and other cities quickly saw severe unrest. By around February 1, the organizers had decided that Egypt could no longer host the event; the World Finals would be postponed and moved, with the place and date to be announced. It was eventually held in the United States.

Now a similar plot had returned. None of this was within the organizers’ control, of course, but their reputation on the forums for being unusually “gifted” at venue selection was firmly established. Many participants were angry. This was a competition, not an ordinary conference, and postponement could seriously affect a team’s form—especially for teams capable of contending for the title.

The pandemic had already delayed the World Finals by more than a year. To catch up, the 2022 and 2023 editions were going to be held together, and now both were postponed. The 2022 World Finals would take place in 2024. Some contestants in this “International Collegiate Programming Contest” had graduated and worked for two years; no one knew how long it had been since they qualified. Bring them back after all that time and ask them to compete—what could possibly go wrong?

The contestants needed somewhere to direct their frustration, and the organizers received all of it.

After overcoming every imaginable obstacle, the World Finals finally took place in Luxor in 2024.

I was eligible for a visa on arrival in Egypt, so entry was no longer the problem. By then I had also received my US green card, making the return trip straightforward. Luxor was still not especially easy to reach. The flights and connections took long enough to remind me that I was no longer built for endless travel days.

After entering Egypt, I had to connect in Cairo for Luxor. I had not expected the trip to deliver two unpleasant surprises before I even left Cairo. During this particular transfer, I somehow went through three separate security checks. Do not ask why I had left the terminal’s transfer route. I could have remained airside, but the signs confused me so thoroughly that I followed them straight out of the airport.

The three checks were a light screening at the terminal entrance, a more substantial one before the departure area after presenting a boarding pass, and another substantial screening assigned to the individual gate.

That final checkpoint was where the trouble began. A single officer was operating it and seemed to have considerable discretion. Absolute power, as the saying goes, has its risks; I had not expected to receive such a direct demonstration.

The officer asked me to open my suitcase. He pointed to my steam eye mask and asked what it was. I explained that it was a warming eye mask for relieving fatigue. He said it was not permitted. At first I did not understand the significance. It was an unfamiliar item, I thought, and perhaps he was simply being cautious.

He placed the eye mask to one side, then pointed to the case for my electric toothbrush. What was that? An electric toothbrush, I said. Not permitted. By now I was thoroughly confused. The toothbrush joined the eye mask.

Finally, he pointed to my Apple earphones. What were those? Obviously, earphones. Not permitted. He set those aside as well. I had no idea what he was trying to accomplish.

He apparently realized that I still had not understood, so he asked one more question. The moment he said it, everything became clear.

“Do you have money?”

Now I understood. In my view, this was no longer inspection but an open demand for a bribe. There was little I could realistically do. I reached into my pocket with what must have been an expression of belated comprehension. He immediately pressed my hand down and asked what I was doing, pushing both my hand and the money into my backpack on the table. Another moment of disbelief: he knew perfectly well that soliciting money was wrong. Was he trying to keep it out of view of the cameras?

I searched through the cash inside the bag and drew out a ten-pound note. He looked dissatisfied, said “no, no, no,” and indicated the hundred-pound note instead. What choice did I have? I handed it over. He smiled and said, “My friend, now everything is fine.” My earphones were suddenly fine and went back into the bag. The toothbrush and eye mask underwent the same miraculous transformation. Then he let me through.

I was badly shaken and wanted only to leave before anything else happened. I was fortunate that I had exchanged some US dollars for Egyptian pounds on arrival. What if I had carried no local cash? Could he simply point to my dollars, declare those “not permitted,” and take them? What exactly was I supposed to do?

Sitting near the gate, I searched online and found numerous accounts from travelers who said they had encountered similar situations at Egyptian airports. Many described being pressured for money by security personnel. I also found people claiming that solo travelers who appeared to have no assistance were easier targets. In an unfamiliar country, was I really going to demand a supervisor and begin an argument? There was no guarantee whom the supervisor would support, and I was not eager to discover how much worse the situation could become.

Nor did I appear to be the only person affected that day. While I was sitting there, I overheard two Chinese women nearby discussing how they had just had money demanded from them as well.

The experience was not finished. In an airport restroom, after I washed my hands, there was soap and paper available beside the sink. A man who appeared to be a cleaner held soap out to me; I declined. When I went to dry my hands, he offered me a packet of tissues, and without thinking I took two. As I tried to leave, he blocked the doorway and held out his hand for a tip. He said only one word—“tip”—and nothing else. I began to suspect, unfairly perhaps, that he had reserved his entire English vocabulary for this particular business model.

Once again, money was being demanded. What was I supposed to do—start a fight in an airport restroom?

By then, my impression of Egypt had fallen into its lowest category. I had seen a cynical travel joke online: if you never visit Egypt, you will regret it for life; if you do visit, you will spend a lifetime regretting that instead. After those two encounters, the joke suddenly felt uncomfortably apt.

I looked up some figures available online at the time. Some put the monthly salary of a full professor at an Egyptian university at around EGP 20,000—roughly US$400, or about one-sixth of what an ordinary PhD student might receive in the United States. Now consider a purely hypothetical calculation: if this security worker worked twenty days a month and managed to extract 100 pounds from only ten people a day, his additional income would exceed that professor’s salary. How is that remotely reasonable? Shouldn’t this be cracked down on?

The flight to Luxor was uneventful, thankfully. The organizers had arranged accommodation at what was billed as a “luxury resort” on the Nile. It fell some distance short of what I would normally picture under that label, but it was clear that the organizers and local hosts had provided quite respectable conditions with what was available.

The hotel stood directly beside the river, with views of the Nile at night.

As a resort, it even had its own zoo. One of that year’s contest problems happened to use a zoo as its setting, so we went there to take a photograph for the problem statement—not the photograph below.

The organizers’ rest-day excursion began with a boat ride on the Nile. It was, honestly, an excellent experience. Sitting in a small boat with a light breeze does not sound extraordinary in itself. Remembering that the water beneath us was the Nile, traditionally regarded as the world’s longest river, made it feel considerably more consequential.

We then visited the Karnak Temple Complex. It felt as though the mysterious scenery of a film had entered the real world, and that a mummy might emerge at any moment.

Outside the official itinerary, the judges found a little spare time and arranged a private tour to the Valley of the Kings, the Valley of the Queens, and several nearby sites.

The sheer number of ancient sites in Egypt was remarkable.

Soon it was contest day. The broadcast set stood outdoors. It was atmospheric, though it also looked like an excellent place to meet a large number of mosquitoes.

The contest hall itself was a temporary structure. There may not have been a permanent venue anywhere in Egypt capable of holding two World Finals and more than 260 teams at once, so one had to be built. Imagine something like a gigantic, opaque, double-layered plastic greenhouse. The zones between the outer and middle layers belonged to staff and were inaccessible to contestants; inside the final layer was the enormous competition hall.

Whatever else one might say, the air conditioning was excellent. The hall remained impressively cool. Given the temperature outside, competing without it would have been deeply unpleasant.

The judges shared an office with the contest-system staff. “Office” understated its size; it resembled a university computer laboratory. The two groups traditionally seem to share a room because together they determine how the contest runs and how submissions are judged. If anything goes wrong, everyone needed for the discussion is close at hand.

The two World Finals used independent problem sets and numbering. Some problems appeared in both contests, but under separate identifiers, so looking at the other scoreboard did not reveal which problem corresponded to which. We had also thought carefully about selection. We wanted the problems unique to each contest to differ enough that the two champions could not be compared too directly. If the sets and contest trajectories had been nearly identical, and one champion finished a problem ahead of the other, spectators could easily have concluded that the winner on the “weaker” side had merely been fortunate that the strongest teams were elsewhere. Being mocked even after winning a World Finals would have made for a miserable experience.

As when I had attended as a coach, five hours sounded long in advance. In practice, one could stare at the scoreboard and discover that two hours had vanished. The contest passed remarkably quickly.

During the competition, I was invited to record a solution explanation for one problem. The video remains on the official World Finals YouTube channel.

Those five hours of judging were, ideally, very dull. Judges and problem authors do most of their work before the contest; if they suddenly have a great deal to do during it, something has gone wrong. Our most common task was receiving teams’ clarifications, debating English grammar, and eventually replying with no comment. The most entertaining clarification we received asked: “Every time I press 0 on my keyboard, the computer shuts down. Is there any hope?”

Fortunately, that had happened during the rehearsal the day before and had already been fixed. In the actual contest, the affected team would understandably have been raising every alarm available.

Finally, congratulations to Peking University for an extraordinary comeback and the championship. Their first solve of problem S at 276 minutes prompted the entire judge room to cheer. When they solved X at 292 minutes, the place erupted again—by “the place,” of course, I mean only the judge room. The on-site scoreboard was frozen, so the audience would see none of it until the reveal.

By comparison, the winner of the other World Finals felt almost anticlimactic to me. With problems of roughly similar difficulty, that champion finished one problem behind and appeared thoroughly overshadowed. The comparison we had hoped to avoid happened after all.

The closing and scoreboard-reveal ceremony was held in an open square before a temple more than 3,500 years old: the famous Mortuary Temple of Hatshepsut on Luxor’s West Bank, built beneath the cliffs. The stage stood directly in front of the temple, turning the ancient structure and cliff face into a remarkable backdrop. We had visited during the day. At night, however, the foreground lighting was so bright that the background was barely visible to the eye and almost impossible to photograph. Dinner was served during the ceremony. That evening’s food looked rather like the contents of one enormous communal stew pot.

Unfortunately, we judges already knew the result and had already celebrated, so the reveal itself was rather uneventful. Asking contestants on stage to guess their ranking was also painfully awkward; their expressions suggested that they would gladly have disappeared from the broadcast. Peking University’s penalty time was high, so the dramatic uncertainty of their comeback ended while the silver-medal places were still being revealed. Once their ten problems carried them into first, they never came down.

The day after the contest, everyone went home. I flew directly back to the United States without considering a day in Cairo. I had travelled all the way to Egypt and never seen the pyramids, which remains a genuine regret.

I later heard that one of the American judges took a 3 a.m. flight to Cairo the following day, joined a day tour, and then boarded an 8 p.m. flight back to the United States. He was already sixty. I could only admire both the stamina and the willingness to subject himself to that schedule—and wonder why the same idea had never occurred to me.

That story changed the way I approached later trips. Whenever I found myself somewhere new, I began by asking whether I could fit in something extra simply because I was already there. Travel is, after all, a form of willingly chosen inconvenience. There is no need to lock every hour in advance; sometimes it is better to follow one’s mood and improvise.

That September, I was back for the annual World Finals—for the third time that year. It should have been once that year and twice the year before, but the Egypt contest had been moved into 2024 as well.

This was my third World Finals as a judge. I felt much calmer than before, as though it had already become part of the routine.

At the time, Chinese citizens could enter Kazakhstan without a visa. I assumed this would be my smoothest trip yet. International air travel promptly taught me otherwise.

I had originally booked a round trip on Lufthansa: San Francisco to Frankfurt, then onward to Astana. The uncertainty was the connection in Frankfurt, which required taking the airport train to another terminal. I could not determine whether that meant formally entering Germany. In theory, an international hub as large as Frankfurt surely had a fully enclosed transit zone with unrestricted access to the train. Yet after searching both the airline’s and the airport’s websites, I could find no definitive statement that my particular connection would be fine. Everything I read seemed to imply that there was a separate “international transit area” and that no entry formalities were required as long as one remained inside it. I was never entirely certain, but chose to trust that interpretation.

The larger problem came three weeks before departure: the return flight from Astana to Frankfurt was canceled. That invalidated the entire itinerary. Ordinarily, when one flight is canceled, the airline moves you to another departure. But there was only one flight that day. Taking the next day’s flight would not work either, because the onward service from Frankfurt to the United States was also on an every-other-day schedule. I would have been stuck at Frankfurt Airport for more than twenty-four hours. That was impossible for me.

The route was no longer viable, so I had to rebook everything. I received a full refund, but the process was troublesome, and airfares generally rise as departure approaches. I searched again and found no workable European connection for my own passport and visa situation. One option went through Britain but required changing airports; I did not have a British visa. Another involved twenty hours at Warsaw Airport, with the two legs operated by different airlines. I could not establish whether I would need to enter Poland, and I did not have a Schengen visa. Looking through those fares was deeply discouraging. Some well-timed options, including connections through Istanbul, had already disappeared because the date was so close.

Was that it? Was I simply not going?

Once I calmed down, I realized that Astana was almost exactly twelve hours ahead of San Francisco. Why not look in the other direction? I began searching for an eastbound route around the world, and there it was: the best place to “connect” was China. Google did not show such options because they were not really connections at all. They required separate tickets and, in all likelihood, entering the country. I searched independently for a round trip between the United States and China and another between China and Kazakhstan. The timings fit remarkably well, and entering China posed no problem for me. The decision was immediate. I booked it.

Beijing Airport saved the trip. Without that route, I doubt I would have reached the World Finals at all.

After considerable effort, I finally arrived in Astana. Talking with others, I learned that many had also been booked on the canceled flight and had rearranged their travel. Those carrying American passports had far more flexibility when connecting through Europe and avoided most of the complications I faced.

One notable change that year was the arrival of Gennady Korotkevich—tourist, then ranked number one in the world on Codeforces—on the judging team. Judging requires strong problem-solving ability, but not necessarily the ability to solve at competition speed. Many judges either do not compete online or do not have especially high ratings. As a result, when a judge occasionally explained what had happened during a contest on a forum, someone would ask, in effect, “And who are you?” That particular problem was unlikely to arise again.

It was also the first year that we used AI to generate illustrations for some of our problems. The results were excellent.

In the days before the contest, we found a free day for sightseeing in Astana. The main excursion was simply a walk to the Astana Grand Mosque.

It looked exactly like the photographs online. The interior was exceptionally intricate, and obtaining a photograph with no one in it was an achievement in itself.

On the walk back, we saw many posters like these along the street. I could not read the text, but the images appeared to advertise traditional Kazakh sporting events. A sincere question: does training an eagle count as a sport?

The opening ceremony was held in the main hall of the Presidential Center. Security was nearly as strict as at an airport. Since almost every bag had to be opened and inspected, the official advice was not to bring one. Given the schedule, however, contestants who had joined the preceding activities could hardly avoid carrying bags unless they handed them to their coaches to take back to the hotel. Many arrived with them.

I had skipped the earlier activities entirely and reached the venue very early. No one was there yet except the welcoming band.

I then watched the contestants arrive with their bags. An hour later, security was still processing them.

There is little to say about the opening ceremony itself. After attending more of them than I can count, they do begin to resemble one another.

The day before the contest, the organizers arranged another excursion, this time to something resembling a science museum. From outside, it looked like this: a spherical building whose stacked levels were visible through the exterior. Visitors took an elevator to the top, then descended one floor at a time through the exhibits.

Most of the explanatory text in the venue appeared in three languages: Kazakh, Russian, and English. Many of the staff spoke all three, which was impressive. I ran into a former assistant coach from my university who spoke Russian. I asked how different Russian and Kazakh were. To me, the alphabets looked similar—possibly because I could read neither. He said they were very different, entirely separate languages, and that he could not understand Kazakh at all.

This was the contest venue.

Inside were numerous entertainment areas and technology exhibits. That, too, is a long-standing tradition. Contestants can use them during the surrounding days; once competition begins, the coaches and assorted bystanders take over. Downstairs from our hotel there was even a yurt-like structure whose interior looked like this.

On a free afternoon, one could lie down in there and quite happily remain for the rest of the day.

By then, I thought the contest would proceed smoothly. The largest crisis arrived on the evening before it began.

I was at the hotel, had showered, and was preparing for bed. Three calls came while I was in the shower, all of which I missed. When I checked my phone afterward, the message was essentially: serious problem with a problem; come immediately. They called me because I was the author. I will not identify which problem it was. Readers familiar with the complete set may be able to work it out for themselves.

The situation began this way. On the day before the contest, we generally share the problems with the broadcast analysts so that they can learn what each asks and how it is solved. This allows them to record explanations in advance and analyze the contest more effectively while it is under way. The solution to this particular problem began with a case analysis: according to the greedy argument, there were only two cases. As the analysts recorded their explanation, however, the argument felt increasingly suspicious. Why, they asked, were there only two?

In the spirit of proper verification, someone wrote a brute-force solution that enumerated every possibility and selected the optimum. Its output did not match the official data. The brute-force program found a better answer.

That was bad. The exhaustive search was almost certainly right, which meant the official output was wrong and all the judges’ implementations were wrong with it.

It was nearly nine in the evening, with about twelve hours remaining before the contest. Calls went out, and many of us were summoned downstairs. We quickly discovered how easy the problem was to misunderstand. Every one of us who had solved it had independently and quite naturally overlooked the same additional case.

The senior members of the judging team considered how the problem might be changed quickly enough to rescue it. The rest of us asked whether it could be rescued without changing the statement at all.

Something similar had happened at an earlier World Finals. I was not a judge then, but later read the official post-contest analysis. According to that account, on the night before the contest the judges discovered that one problem was fundamentally wrong and could not be repaired, while the problem sets had already been printed, stapled, and sealed. They spent the night opening every packet, removing the staples, taking out the bad problem, inserting a replacement, stapling the set again, and resealing it. The work reportedly lasted nearly all night. By the end, everyone had become an expert staple remover.

Our situation did not appear quite that severe. The missed case mattered only within a particular portion of the input range. If we halved the range, the case would no longer need to be considered. The correction would even look unusually benign: given how the original bound was written, halving it on paper would resemble a simple printing correction rather than a substantive change to the problem. We could have fixed the issue without disrupting the contest, with only a general announcement at the venue.

The senior judges began calling the relevant people to explain that this might be necessary the following morning and that preparations should be made.

The rest of us continued asking whether the problem could survive unchanged. To our surprise, it could. We had indeed missed a case, but apparently only one. Adding it would not change the time complexity of the intended solution. Several of us began modifying our implementations. By then, it was ten o’clock.

Twenty minutes later, the first revised program was ready. Five minutes after that, mine was ready too. Over the next stretch of time, more implementations arrived, including some rewritten from scratch. We cross-checked them against one another and found no discrepancy. We then tested them on cases generated by the brute-force program, and those results matched as well. We now had a correct solution. The crisis had been contained.

We reran the entire dataset with the new judges’ implementation and added many tests for the newly identified case. By the time everything was complete, it was half past eleven. The good news was that no announcement was needed and the problem statement required no change; the issue had been resolved without affecting the contest at all. The bad news was that the problem had become considerably harder. The missing case was genuinely difficult to notice. If a submission failed during the contest, a team would have little way to know whether the implementation contained a bug or whether the underlying analysis had missed a case. If necessary, they might have to spend precious computer time—three contestants share a single machine—writing a brute-force solution for cross-checking.

The next morning, the contest began normally. As the problem author, I soon realized that it was much harder than I had originally imagined. Even setting aside the extra case, I had expected many teams to submit and then fail because of it. In reality, there were hardly any submissions at all. The first accepted solution did not arrive until three hours into the contest, making it one of the three hardest problems in the set.

We watched every submission to it closely. At the time, every team’s first attempt omitted the additional case. Not one succeeded immediately. The trap was every bit as effective as we had feared.

In other words, had we not found the issue the previous night, the contest might still have proceeded normally. No one would have noticed, and no team would likely have been affected, because no one identified the missing case before first receiving a wrong answer. Only much later, after the data became public, would someone probably have returned to perform the postmortem.

During the contest, a judge with time to spare gave the problems to several AI systems. If I remember correctly, they produced complete, correct programs for only two or perhaps three problems—and not even the easiest ones. At that point, their competitive-programming ability still varied wildly and clearly needed both greater consistency and further improvement. Who could have imagined that barely a year later, AI systems would be solving entire ICPC-style problem sets?

Finally, congratulations to Peking University on another championship. A penalty-time lead of nearly 300 was itself a display of strength.

The most painful result was Tsinghua University’s. They finished one test case short of their first world championship. Looking only at the scoreboard, an outsider would see two problems with wrong submissions and think the result unfortunate. As judges, however, we could see that on one of those problems their program failed only the final test case. We examined that test repeatedly and found nothing remarkable about it, yet they never located the bug. Had they corrected the failure and passed that submission, they would have solved one more problem and won the championship. It was extraordinarily close.

Our journey to Antarctica began in the capital of Argentina.

By long-established international custom, every international trip begins with a visa. This time, the Argentine visa process handed me a particularly large complication.

Under the rules in effect when we applied, Chinese passport holders with a qualifying US or Schengen visa—and visas from several other countries—could use a simplified entry arrangement. A US green card, however, did not qualify. I found this baffling. A traveler with a US visa was apparently not considered likely to remain in Argentina, while a US permanent resident might be? From my perspective, the distinction made no sense.

Rules were rules, so I needed an Argentine visa. The application itself was not especially complicated. It required the familiar collection of travel plans, hotel and flight bookings, bank statements, and similar documents. The difficulty was timing. In our case at the time, applying through the Argentine consular system in the United States meant that we could not submit until roughly ninety days before the trip. Our flight would arrive on January 12, 2025, so the first practical filing date was a business day after about October 14, 2024.

That alone would have been manageable. What we found online at the time suggested that applicants in China could apply earlier and might receive visas valid for six months or even a year. In the United States, we could apply only ninety days ahead, and the visa itself was valid for entry for exactly ninety days from its date of issue—not a day more or less. That probably explained the filing restriction: apply too early, and the visa could expire before the journey began. We seriously considered returning to China to apply. The documents were submitted online and an interview might not be necessary, so perhaps no one cared where we physically were. After reviewing the requirements, however, we found that applying there would require Chinese income and bank documentation that was even more awkward for us to provide. We abandoned the idea.

There was another complication: Argentine consulates across the United States appeared to have very different working styles. Each had its own website, and online accounts described some as fast and others as slow. The Los Angeles office serving California was singled out for particularly severe criticism. The office in Illinois was said to be unusually quick. We even seriously considered listing a friend’s Illinois address to see whether we could apply there, though we never acted on the idea. In the end, I had emailed that office and received no response for two months. I remained unconvinced by its reputation for speed and decided not to complicate matters further.

We applied through Los Angeles. Its pace was exasperating. The email acknowledging our documents was automated and said to expect a reply in five to ten business days. Ten business days passed without one, so I wrote again. Another automated response now advised waiting fifteen to twenty business days. Five more days passed; I sent another message and received the same automation, this time promising twenty to twenty-five business days. It also added that applications submitted after November would not be processed until the following year.

From where we were sitting, an entire month had passed without the application moving at all. No matter when I wrote, the expected wait simply stretched another ten days into the future. The online accounts we had read—of an exceptionally slow consulate issuing visas so close to departure that travelers nearly had to change their flights—were beginning to feel entirely credible.

This continued until roughly the end of November. We were deeply anxious and had no useful way to intervene. Email produced only meaningless automated replies. Reaching anyone by telephone seemed to require a minor miracle.

At the end of November, the consulate finally emailed to arrange an online interview in early December and asked when we were available. There was nothing to consider: we were available whenever they wanted. Name the time and I would take leave from work if necessary. Who knew what fresh complication might appear if we delayed?

I can only say that we were fortunate to have submitted on the first business day we were eligible. Had we waited until November—which would have meant postponing the application by only about two weeks—the entire Antarctic journey might genuinely have been cancelled.

On interview day, another complication duly arrived. A half-hour interview began thirty-four minutes late. This time we were less alarmed because it was a WhatsApp video call and we already had the interviewer’s contact. Ten minutes after the scheduled time, we sent a very polite message whose underlying question was essentially, “Where are you?” Predictably, there was no response. Persistence eventually paid off: after waiting in place, we finally reached the interviewer. He said the previous interview had run long. Fine. He controlled the visa; we were hardly in a position to negotiate.

The interview itself went smoothly. Our application was fairly complete. Comparing it with the checklist, the interviewer said we needed only two additional documents. We had already submitted similar material and thought it sufficient, but now he specified exactly what he wanted. He also helpfully told us not to wait for acknowledgment of the new documents before mailing our passports. We could send them immediately and let both processes proceed in parallel. That is what we did.

The brief interview ended, and we emailed the requested files at once. We promptly received another automated reply recommending a wait of twenty-five business days. There was no way to know whether anyone had actually received them.

The next stretch was even more nerve-racking, because now we no longer had our passports either. In the end, the documents had indeed arrived. Roughly two weeks after mailing the passports, we received them back with fresh Argentine visas attached. It was already December 23, less than three weeks before departure.

The lesson would seem to be that an Argentine visa application should begin as early as possible; delay could be disastrous. On reflection, that advice is probably useless to most readers here. Chinese readers applying in China could start much earlier, while American readers did not need a visa at all.

In any case, the journey went ahead.

Why begin in Buenos Aires? Ships to Antarctica departed from Ushuaia, and flying there from the United States inevitably involved a connection in Buenos Aires. This was more than the recurring logic of “we have come all this way, so we may as well look around.” Many of the connections we found for our itinerary involved changing airports in Buenos Aires. Yes, the city has more than one airport. They were not enormously far apart; without traffic, the drive was on the order of a few dozen minutes.

Given that arrangement, we had already come this far…

Our Antarctic itinerary also began on a Wednesday, which meant leaving the United States no later than Monday around midday. We would have to take the entire week off regardless. Why not depart on the previous Friday evening instead? The same amount of leave would buy us more time in Argentina. Once the vacation days were committed, we might as well use them.

All told, including arrival day, we spent three days in Buenos Aires.

We arrived at midday. At immigration, Argentina immediately gave us another taste of just how relaxed things could feel here. The immigration officer processed our entry while watching something on his phone—and he was genuinely absorbed in it. Something about our passports apparently required further checking. He took them into a back office and told us to wait where we were. As he walked away, he carried the passports in one hand and his phone in the other, continuing to watch the video. I had visited more than twenty countries by then, but this was a first.

Entry itself went smoothly. Whether the phone prolonged our wait was another question, but there were no actual problems. He returned from the back office and admitted us immediately.

We then took an Uber from the airport to the hotel. The driver managed to surprise me again: he used his phone while driving. There was little I could say beyond the obvious—whatever else one might think, keeping one’s eyes on the road seems like a fairly basic requirement.

After resting at the hotel for the afternoon, we booked a tango dinner that evening. The concept was simple: we ate dinner in a small venue while tango was performed on stage. Browsing Viator, I found that dinner-and-tango shows were among the most popular activities in Buenos Aires, with a great many providers. I chose one more or less at random.

I have no particular assessment of the dinner; it was an ordinary meal. The tango, however, must have been reasonably authentic Argentine tango. If a performance this commonplace in Buenos Aires did not qualify, I was not sure what would.

On our second day, we took a full-day tour of Buenos Aires’ popular sights. Before the trip, we had read online that Buenos Aires could be quite risky, with motorcycle or scooter snatch theft among the incidents travelers reported. We therefore bought two phone tethers and strapped our phones to our wrists. The dark joke was that, if a rider tried to snatch one, either the phone stayed or the hand went with it. Our guide also warned us that, however safe the streets might appear, we should avoid displaying anything valuable. Carrying a DSLR openly in one hand, for example, was precisely the sort of invitation a thief might notice. Fortunately, no one tried to rob us that day. Whether we were lucky or conditions had improved, I could not say.

Perhaps the most famous stop was Caminito. Its name means something like “little path” in Spanish.

We also visited this bookshop in central Buenos Aires. We tried to find a Spanish-language edition of One Hundred Years of Solitude to bring home for a friend. Unfortunately, our Spanish was too poor and we never located it. I would imagine the shop probably had a copy somewhere.

On the third day, we visited a ranch outside Buenos Aires for a full-day countryside excursion. To be honest, the itinerary felt rather thin. I spent most of the day either sitting in a vehicle or waiting without much to do. We did see an impressive equestrian display, beginning with a rider facing backward on the horse—a fine demonstration of harmony between human and animal.

The performance gave me a useful new standard. From now on, whenever someone tells me they know how to ride, I know exactly what demonstration I am going to ask for.

That concluded our time in Buenos Aires. Next came a flight to Ushuaia, the end of the world.

We had reached Ushuaia. The journey to Antarctica was about to begin.

Antarctica. I had been thinking about this trip for years. Long before we went, I had read that expedition berths were notoriously difficult to secure and generally needed to be booked about a year in advance. I eventually made our reservation the previous April. Why April? Because until then I had been occupied with Egypt, and the third-party tour listings I was watching continued to show availability. I assumed I could simply book after I returned.

That was when I learned how naive I had been. Of course those travel-agency listings continued to show space: they were third-party sales pages, and their inventory did not update automatically. The sites even said explicitly that customers should contact them before placing an order. If the voyage was full, an agent could simply say so. Whether I actually secured a berth was hardly the website’s problem.

I understood all of this only after spending considerable time in April researching how Antarctic travel worked. The first decision was the expedition company. Some companies operated their own ships all the way to Antarctica, which meant there was no need for another intermediary. I could not shake the feeling that adding a middleman to a trip whose least expensive berth already approached US$10,000 would only make an expensive journey cost even more.

There were still quite a few operators to compare, and the advice quickly became overwhelming. Antarctic landings involve matters such as site capacity, passengers going ashore in groups, and the scheduling of Zodiac boats. In broad terms, the larger the ship and the more passengers aboard, the more constrained landing operations tend to become. A larger vessel is generally steadier and less likely to induce seasickness, but may leave less time ashore; a smaller vessel tends toward the opposite trade-off. The staffing ratio also matters. With too few expedition staff, guides, and crew for the number of guests, service can suffer—an important consideration when the ship will be home for many days. Then came ratings for every other conceivable detail. The more I read, the less simple the choice appeared.

In the end, I trusted the recommendation in one article and chose Lindblad Expeditions. It was said to be relatively expensive, but also highly professional and known for excellent service. One factor carried disproportionate weight with me: the company had a longstanding collaboration with National Geographic, and the program was called National Geographic-Lindblad Expeditions. I knew almost nothing about Antarctic expedition companies, but I knew National Geographic. That familiar name was reassuring enough.

After choosing the company, we had to choose a departure. There were many dates, roughly one each week, but the itineraries were not identical. Some voyages sailed from Argentina and returned there by ship. Others ended with a flight to Chile. Still others began and ended in Chile, using flights in both directions.

What we had heard at the time was that the Drake Passage between Argentina and Antarctica could be formidable, and was often described as one of the world’s most dangerous stretches of sea. A glance at the map helps explain its reputation. The passage lies between South America and Antarctica, along a confined ocean corridor traversed by the Antarctic Circumpolar Current. The high southern latitudes also experience powerful westerly winds, sweeping around Antarctica with little continental landmass to obstruct them. Strong current, persistent wind, and ocean swell combine to give the Drake its famously rough conditions.

I am severely prone to seasickness, so I would have avoided the passage if possible. By the time I booked, however, the fly-both-ways option had no availability on dates that suited us; the alternative was to wait until late February, which we ultimately decided against. A round-trip voyage by ship was two days longer than sailing south and flying back, and cost several thousand dollars more. The less expensive choice was obvious to me, and there seemed little reason to put myself through the Drake twice. We therefore chose to sail to Antarctica and fly back to Chile.

That decision meant I needed an Argentine visa. Had we flown both ways through Chile, I would have been eligible to enter Chile without a visa under the rules that applied to my circumstances at the time—a Chinese passport together with a U.S. green card.

The Argentine visa process had already provided more than enough trouble, as described in the previous entry, so I will not repeat it here.

After overcoming all of those obstacles, we finally arrived in Ushuaia. The expedition staff met us and took us to the hotel, where they promptly “took possession” of our passports. In less dramatic terms, they temporarily collected them to complete the necessary travel and expedition formalities.

At the welcome dinner that evening, our guide introduced himself with suitable ceremony: Michael Jackson. In his own words, this was not a joke; that was genuinely his name. When he was born, the singer Michael Jackson was still an infant himself, so his name clearly had nothing to do with the Michael Jackson who would later become a global star.

The next day, we visited a nearby national park. To be honest, the outing was fairly modest.

We then visited Ushuaia’s well-known Les Éclaireurs Lighthouse.

We could already see many penguins on the island, and our fellow travelers were visibly excited. None of them could have guessed that, within a couple of days, we would see what felt like dozens of times as many.

That evening, we boarded the ship that would carry us to Antarctica: the National Geographic Explorer.

The Antarctic journey had officially begun.

After we boarded, the ship did not leave port. The wind and seas were too severe for the Drake Passage. Based on what we were told at the time, waves on a typical crossing averaged around five meters. Conditions below ten meters might still be considered; once they exceeded ten, departure was essentially out of the question. That was the situation that evening. We had been scheduled to sail immediately, but departure was postponed until the following day.

Passengers were therefore allowed to go back into Ushuaia for the evening, provided they returned before midnight. We stayed aboard. We genuinely had no idea what else there was left for us to do in Ushuaia. Apparently, quite a few people went into town for the bars.

By the next morning, the passage was still closed to us. It was deeply frustrating, but there was nothing to be done. It felt as though our Antarctic journey had lost an entire day before it had even begun—a painful bargain at these prices.

That afternoon, the captain finally announced that we could depart. At five o’clock, accompanied by one long blast of the ship’s horn, we left the harbor and headed toward the Drake Passage.

At seven that evening, I even took a shower. We had not yet fully cleared the channel south of Ushuaia, and the water remained relatively calm. I had no idea how serious matters were about to become. I simply went to bed.

Sometime after midnight, I woke to metallic clanging in the cabin, as though something were rolling back and forth across the floor. It was the metal water bottle we had been issued. Despite sitting on a shelf with a guard rail, it had escaped and was roaming the room. Fortunately, I could reach it from the edge of the bed without standing up. I put it in my bag. Realizing how violently the ship had begun to move, we took our seasickness medicine and went back to sleep.

The following morning, when I tried to get out of bed, everything fell apart. We were told the waves were around six meters that day—roughly average by the standards of the crossing. For us, they were already far too much.

I sat up. I lay back down. I sat up again, then lay down again. After several rounds, the attempt to get up was officially abandoned. The instant I sat upright, I became dizzy. Within seconds, nausea followed. There was nothing to do but lie flat. The seasickness tablets we had brought did nothing. We also applied the motion-sickness patches we had packed. Those did nothing either. We remained profoundly seasick.

We began to wonder whether our medicine was simply too weak. Someone had to volunteer for the doomed expedition to the reception desk on our deck and ask for stronger medication. That someone was me. I walked for a little over ten seconds, stood for five seconds while asking for the medicine, and walked the ten seconds back. The first thing I did upon returning to the cabin was rush to the toilet and vomit. It was the first time I threw up on this journey, but not the last.

I felt slightly better afterward, but I still had to remain horizontal. Getting up meant immediate disaster. We took the medicine supplied by the ship, and it too seemed useless. Our resistance to seasickness was apparently so poor that no remedy could save us. As I experienced it, lying down was almost fine. I could feel the ship moving violently and could readily imagine why I had just been sick, but as long as I stayed flat, the problem remained manageable. The moment I sat up, the feeling returned. I could last perhaps a minute before needing to vomit. Standing reduced that to thirty seconds at most.

So we lay in the cabin, incapable of doing anything. We missed breakfast, and then we missed lunch. A new problem emerged: lying down kept the nausea under control, but now it felt as though our blood sugar was dropping. There was no choice. We had to call for help.

I moved to the chair beside the telephone and called the ship’s doctor. “Can you come to us?” she asked. I told her there was absolutely no possibility of that; she would have to come to us. She said she would be there shortly. I somehow completed the call during the minute I could tolerate sitting, then went back to the bathroom to vomit again.

I returned to bed, and the doctor arrived a few minutes later. After seeing our condition, she said, in effect, that we were beyond ordinary help. The remaining option was to give each of us an injection of seasickness medication that would put us to sleep, allowing us to sleep through the Drake Passage. Many people aboard were ill on this crossing, she added, and the supply was nearly exhausted. We were lucky: at least two injections remained.

We each received one and promptly fell asleep.

When we woke the next day, the ship had largely cleared the Drake Passage and officially entered Antarctic waters. The most obvious difference was that the seas were calmer.

We decided we were functional again and tried getting up. To be fair, “calmer” did not mean calm. The seasickness had eased considerably, but the symptoms had not disappeared.

We went to breakfast. We had gone far too long without food. Since the evening before last, all I had managed was two crackers eaten while lying in bed the previous day—and I had thrown up a fair portion of those. If I did not eat now, starvation felt like the next item on the itinerary.

On the way to the dining room, we discovered ropes everywhere throughout the ship. At first, we did not understand their purpose. Then we reached the restaurant and found it webbed over with ropes, with passengers holding on as they moved around. So that was what they were for. We also noticed hooks beneath the tables and chairs. Ropes had now been attached to them, securing the furniture to the floor. During our first two days of meals aboard, everything had stood loose. The weather had clearly become serious. Even as we ate, the ship continued to roll, and from the kitchen came repeated bursts of crockery colliding. We could only hope nothing had broken.

We endured breakfast and returned alive. Naturally, our first action was to lie down again. Seasickness behaved like a progress bar in a game. Moving around caused the meter to rise; lying down made it fall. If it reached 100 percent, it rapidly emptied itself—in other words, I vomited.

By noon, the seas had eased further, allowing us to stay up longer and roam a little farther. By afternoon, the water was nearly calm, and we had reached Antarctic waters. I had never expected Antarctica itself to be the calmest place in the region.

Only later did we learn that several formidable passengers aboard scarcely suffered from seasickness at all. They had ventured out during the worst conditions the day before, and someone took this photograph in the lounge.

The motion had been strong enough to send the ship’s grand piano flying. One would think a piano aboard a vessel should be secured to the deck. Were they really reenacting The Legend of 1900 and allowing it to wander about at will? Or had it actually been fastened down, only to be thrown loose anyway?

This was our complete itinerary.

To my eyes, many of these places looked remarkably alike, and I had no idea how to distinguish them afterward, so I have combined them here. The “whale-watching points” on the map were not precise locations either. They were areas at sea where whales might appear; an encounter happened whenever it happened.

We lived aboard the ship, but visiting Antarctica required what felt like an amphibious landing. That description is scarcely an exaggeration. These were the landing craft we used: Zodiac inflatable boats.

For a landing, the larger ship stopped offshore and opened its side door. We descended directly into the Zodiacs. There was no pier at the “shore”—if shore was even the right word—only a completely natural coastline. Staff went ahead to install temporary aids, such as plastic steps. The Zodiacs then approached the beach, we stepped from the boat into shallow water onto those steps, and from there walked ashore. It truly felt like a beach-landing operation.

An Antarctic landing is not a matter of sailing until the scenery looks appealing and stepping ashore. Most Antarctic expedition cruise operators belong to IAATO, the International Association of Antarctica Tour Operators, and vessels coordinate landing sites and times in advance to avoid crowding the same place. Generally, only one vessel lands at a given site at a time, and no more than 100 visitors may be ashore. A ship carrying two or three hundred guests therefore has to divide them into groups. A common arrangement is for one group to land while another cruises in Zodiacs, after which they exchange places.

Individual sites also have their own rules. Some accept only one or two ships per day; some limit the duration of visits. Certain areas are closed to protect penguins, seals, or vegetation, while historic sites may restrict how many people can enter at once. Ships carrying more than 500 passengers cannot land passengers and are limited to cruise-only operations.

The shipping company and expedition team handled most of this scheduling and coordination behind the scenes, so ordinary passengers rarely noticed it. Each evening aboard our ship, Michael Jackson told us where we hoped to go the next day. Antarctic weather and sea ice change rapidly, however, so even a reserved landing could be canceled or replaced at short notice. Put simply, Antarctic landings meant scheduled times, one ship at a site, no more than 100 people ashore, and whatever additional rules applied to that particular location.

For each landing, we wore tall waterproof boots, waterproof trousers over our regular clothes, down jackets, and life jackets. We were equipped from head to toe. Environmental controls in Antarctica were strict, with great care taken not to carry organisms or pathogens from one landing site to another, particularly on footwear, clothing, or equipment.

If our boots stepped in anything at one site—most often penguin droppings—they had to be scrubbed clean before we could reboard. Staff helped with the cleaning. Clothing and equipment were also supposed to remain free of soil and biological residue; anything contaminated had to be cleaned upon returning to the ship. The expedition even supplied trekking poles. Because their tips touched the ground, those too had to be scrubbed afterward.

Our expedition team was as professional as advertised and followed the rules rigorously. During the voyage, however, we encountered another vessel landing seemingly at will. Our guide said that our ship had reserved the site and that he had not seen any arrangement for another vessel to be there at the same time, so he believed they were probably violating the landing plan. In the spirit of everyone doing their part for environmental protection, our group reported them.

At our first landing site, I saw large numbers of seals. They behaved rather like a pack of wolves. They would be lying lazily on the ground, perfectly content, until one began calling. Several others would immediately join in, raising their heads and howling toward the sky. We were told they were competing for dominance.

At subsequent landings, penguins began appearing in great numbers.

This was my first portrait taken in Antarctica.

Anyone who has watched a penguin defecate knows that the result is remarkably forceful: a thin white line shoots out behind it, tracing a graceful—if that is really the word—parabola. Now the white lines around the nests make sense.

I also recorded an excellent video of penguins fighting. Video is less convenient to publish here, however. Perhaps next time—which is what one always says.

We also went out in Zodiacs to observe whales at close range. Encounters depended entirely on luck. Whether we found any whales at all was uncertain. The larger ship adjusted its course according to where whales had been seen and moved toward areas they frequented, which became the customary whale-watching zones. Even there, luck determined how close an animal might come.

Our luck was exceptional. As our boat moved slowly along the whales’ direction of travel, one swam beside a Zodiac ahead of us and began circling it.

We were still remarking on the extraordinary luck of the other boat when the whale came directly toward ours. It surfaced beside us, less than two meters from the edge of the boat. Its fin rose above the water so close that it seemed almost within reach.

I recorded a video filled with the exclamations of everyone aboard. The final image above is a frame from that footage, hence its lower clarity.

In retrospect, watching a whale from such close range may have been rather dangerous. This was “only” a humpback, yet it measured more than twelve meters. Our Zodiac could not have been more than six meters long. One careless flick of that tail looked as though it could have sent us flying. Presumably—perhaps—there had not been such an incident before.

We also saw orcas from the larger ship, many times.

During one landing, we climbed a mountain. The ascent felt exhausting, only for us to learn afterward that the summit stood just over 200 meters high. When I told friends about it, their immediate response was that 200 meters hardly qualified as a mountain. Was that not simply an oversized mound of earth?

Under normal circumstances, they would have had a point. Antarctica was not a normal circumstance.

First, this was the panorama from the summit.

I took the obligatory summit photographs.

And this was the route up.

As the photographs show, there was no trail in the conventional sense, only a route through the snow. Climbing here required full cold-weather clothing: down jacket, thermal leggings, insulated trousers, everything. Without them, one would freeze. All that equipment multiplied the effort compared with hiking in shorts and a T-shirt. Even setting that aside, the snow track was difficult. For long stretches, the snow reached around thirty centimeters deep. Each step sank in, and simply pulling a foot free required effort. Nor could we tell what lay beneath. A step might land on ice hidden under the snow and send us sliding. Throughout the climb, we had to remain alert, brace our cores, and make sure each footfall held.

By the time I reached the summit, I was exhausted. About fifty people had set off behind Michael Jackson at the start. Only four remained with him when we reached the top. After we took photographs and began descending, many others gradually arrived. Early in the climb, the guide’s advice had been, “You are nearly there—keep going.” Farther back, it had changed to, “You should turn around. You may not make it back in time.”

We also visited several historic remains in Antarctica. Our guide offered an amusingly simplified description: anything left before 1958 counted as a historic artifact, while anything left afterward counted as rubbish. His explanation was that Antarctic activity changed dramatically around the International Geophysical Year of 1957–58. Huts, equipment, and objects from the early era of exploration might possess historic value. Waste left after the later expansion of scientific stations, however, did not automatically become heritage merely because someone had abandoned it in Antarctica; in principle, it should be removed under environmental rules.

In Antarctica, then, when one abandons rubbish matters enormously. Leave it early enough, and yesterday’s waste may become today’s treasure.

Penguins had already occupied some of the remains.

Other buildings had not yet fallen to the penguin advance.

By any reasonable standard, this building looked structurally suspect. The guide said we were welcome to go inside and look around, but if it collapsed, that was our problem—a warning delivered more as dark humor than legal language. I went in. Fortunately, I supposed Antarctica had no termites and relatively few earthquakes; otherwise, the place might have fallen long ago.

The ship also organized polar activities, including kayaking and a polar plunge.

The kayaking sounded particularly appealing: a two-person boat among fragments of ice in Antarctic waters. It was difficult not to be excited.

The activity depended heavily on weather, largely because Antarctica left little margin for error. Our guide said we could go to the proposed area and proceed if conditions allowed; otherwise, we would have to abandon the plan. We arrived to find excellent weather. The answer was obvious: launch the kayaks.

Calling it an activity site was generous. It was simply a stretch of water beside the Antarctic continent. The location was probably chosen because its geography made calm conditions more likely. That day was clear and windless, ideal for kayaking. Staff went out first, marked a broad area with buoys, and told us not to paddle beyond the boundary. Then we could leave the ship.

This was our kayak.

And this was what it felt like to paddle into the broken ice ourselves.

Naturally, we took photographs.

Then came the polar plunge. A temporary jumping point was assembled near the kayaking area. In practice, two Zodiacs were positioned beside the open door of the larger ship, with a plastic platform of less than ten square meters suspended roughly one meter underwater between them. Participants stood on the bow of a Zodiac, jumped into the sea, swam to the platform, stood up, climbed back into the Zodiac, and returned to the ship.

That was the procedure for people who could swim. Those who could not were allowed to launch themselves directly onto the plastic platform. As long as the entire body went into the water, the attempt counted.

The activity sounded appropriately dramatic. Predictably, I had to sign two additional waivers—documents that felt very much like contracts surrendering one’s life. The plunge was clearly unwise for anyone with conditions such as high blood pressure or heart disease, yet roughly seventy of the ship’s more than 140 passengers participated. As far as I could tell, people around my age were exceptionally rare aboard, perhaps fewer than ten. Nearly everyone was at least ten years older than I was, many more than twenty years older, and gray hair was common. These explorers in their fifties and sixties were genuinely formidable.

The seawater was about 2°C. I had assumed the jump itself would be the worst moment, but it was not. Entering the water happened in an instant, and the entire interval before reaching safety lasted no more than twenty seconds. One simply endured it. Waiting in line was far worse. We stood in the Antarctic wind wearing only swim trunks. Even that was tolerable for a few minutes. At the beginning of the queue, we could wear sandals, but beside the Zodiacs we had to leave them aboard while several people still stood ahead of us. Towels covered the ground there, but they were saturated with icy water. I stood on them barefoot for two minutes and nearly lost all feeling in my feet.

In the end, I completed the plunge. Unfortunately, there is no photograph to prove it.

Back aboard, the doctor stood nearby and handed each participant a special warming coffee. I did not catch a cold, and everything remained normal.

The landscapes seen from the ship were as remarkable as those at the landing sites. An old line of verse came to mind: with the clouds dispersed, moon, sky, and sea needed no further ornament. The clarity of the blue water and open sky was difficult to rival.

Beyond the scenery, life aboard was impressive in its own right. The ship was remarkably luxurious. The lounge bar opened every afternoon and stayed open indefinitely into the evening—as long as someone remained, it remained open—with all drinks included. My only disappointment was that one nonalcoholic drink I had selected remained out of stock until I disembarked. It had looked delicious, which apparently meant everyone else had reached the same conclusion first. The ship also had a sauna, a spa, and a glass-walled panoramic gym. The range of facilities was extraordinary.

Eventually, our journey approached its end. The ship returned to King George Island, where an airport would provide our flight to Chile.

Naturally, something went wrong again.

The airport was rudimentary and bore little resemblance to an ordinary civilian terminal. The runway did not look like a conventional paved surface; from what I could see, it was made entirely of gravel. Taking off and landing there appeared difficult. With minimal facilities and rapidly changing Antarctic weather, flights depended heavily on visibility and conditions. The sky had to be clear, or visibility had to exceed some required distance, before an aircraft could operate.

Our guide said that, in their experience, the usable flight window on a given day might last only a few hours. We therefore spent our final day aboard waiting. Once a window was confirmed, we would take Zodiacs to the island and proceed to the aircraft.

On our scheduled departure day, no window opened at all. Observations at the time also suggested that flying might remain impossible the following day. We should ordinarily have continued waiting, but because operations were definitively impossible for the moment, the captain arranged one more landing. We gained an unexpected additional excursion.

And saw still more penguins.

Attentive readers may notice that these photographs differ substantially from all the earlier ones. Every previous image was taken in fine weather. For several days in Antarctica, both at sea and ashore, we had enjoyed clear skies and excellent conditions. Whether that was fortunate or unfortunate depended on one’s perspective. It made every activity much easier, but it did not feel remotely Antarctic.

This day was different: a full blizzard. The air was cold, the apparent temperature far lower than before, and the wind cut through us. For the first time, Antarctica felt genuinely severe.

Many people aboard expressed the same thought: this was Antarctica. The previous days of sunshine had encouraged the unrealistic impression that the continent was tranquil.

Once back aboard, everyone seemed even more satisfied. We had now experienced an Antarctic blizzard as well. The journey felt complete.

That evening, the guide told us that flight operations would probably be possible the next morning. We should sleep, he said; if a window opened, they would wake us.

At four the next morning, we were dragged from bed. Breakfast followed at speed, then a Zodiac ride to King George Island, another beach landing, and a journey to the airport to await the plane.

As noted earlier, calling the place an airport required some generosity. Around its perimeter stood a few structures that could be described as buildings, and we waited inside until the aircraft was nearly ready to land. We were told that cleaning the facilities was extremely difficult. To protect the environment, we should avoid using the toilet unless absolutely necessary. Whatever we had, we were asked to carry it onward to Chile.

A bus then took us closer to the boarding area, where we continued waiting in what passed for a departure lounge: two plastic tent-like shelters. The wind roared outside, and its howling remained plainly audible through the plastic. At this point, toilets ceased to exist altogether.

The aircraft did finally arrive. One was painted black and white, prompting the guide to call it the penguin plane. When it took off, people nearby became wonderfully excited and shouted, “The penguin is flying!” The old human tradition of inventing one’s own entertainment remained alive and well.

We boarded the second aircraft and flew to Chile.

With that, our Antarctic journey officially came to an end.

The difficult journey home began in Chile.

Well, in truth, it had begun much earlier. The complications started the moment we tried to book the tickets.

Flights in South America were remarkably difficult to arrange. Getting to Buenos Aires on the way out had been manageable—it was Argentina’s capital, after all. We had also invoked our usual principle of “since we’re already going to be there” and turned the connection into a two-day stay. That gave us more flights to choose from and made the booking much easier. Had we tried to fly straight through to Ushuaia, even the outbound journey would have been difficult.

On the Chilean side, our connecting itinerary back to the United States had to begin in the small town of Puerto Natales. Our charter from King George Island would first land there on the South American mainland, so that was where the rest of our return journey had to pick up.

And those tickets…

In our online research, we came across some sharply negative reviews of travel sites such as Expedia, including individual accounts from people who said they had booked online only to discover at the airport that no ticket had actually been issued. That sounded both extreme and rather implausible, but the anecdotes were there. They made us nervous enough that we decided to book directly with the airlines.

The Latin American options we could find at the time were mostly on carriers such as Copa Airlines and LATAM Airlines. We checked each of them, then worked through the major American carriers as well, including United Airlines and Delta Air Lines. Eventually, with considerable effort, we found a few itineraries that met our needs.

They all shared one problem: among the routes we found from Puerto Natales to the United States, not one was operated throughout by a single airline. Every itinerary used a Latin American carrier for the portion within Latin America—or, more precisely, outside the United States—and then switched to an American carrier once inside the country.

That was entirely reasonable. These were sold as connecting itineraries, so in theory it should not have presented much of a problem. And yet…

The first warning came when we tried to choose seats. Book through the Latin American airline’s website, and we could not select seats on the American flights; book through the American carrier, and the reverse was true. Since the Latin American portion made up most of the journey, we considered it more important and decided to buy through that airline’s site. Random seats on the domestic American legs seemed an acceptable compromise.

If seat selection had been the only issue, that would have been fine. We skipped it, continued through every page, reached the final step, and tried to pay. The order failed. We tried again and again, in every way we could think of, and received an error every time.

In the end, we had no choice but to book through Expedia after all. We might as well have surrendered earlier and spared ourselves the effort.

That, however, was only the beginning. About four months in advance, we booked the full itinerary: Puerto Natales to Santiago, Santiago to Los Angeles, and Los Angeles to San Francisco.

From the moment we booked it, the schedule never stayed still. On our particular itinerary, something changed about every two weeks. Each adjustment was fairly small—perhaps an hour—but there were so many of them that the schedule gradually became absurd. At first we went online to review and confirm every change. Eventually, we stopped trying to keep track. The one benefit was that, whenever we chose not to accept a change, the system at the time allowed us to modify the entire itinerary without charge.

That turned out to be a lifesaver.

As I described in the previous Antarctica entry, our flight from Antarctica to Chile could not depart as scheduled and was delayed by nearly forty hours. Every onward flight therefore had to be rebooked. The tour operator that ran our ship also offered a flight-booking service, and in circumstances like these, having them manage the connections would undoubtedly have been convenient. I cannot judge the quality because I did not use it, though I have every reason to believe it was good. The price was another matter. Our entire economy itinerary from Chile to the United States cost a little over $1,000; the booking service alone was priced at $500. That was beyond what I was willing to pay.

Once it became clear aboard the ship that our flight would be delayed, we used our free-change option. It was no minor revision: we pushed the trip back by a full day and even changed where we would enter the United States. By then, the timing of the Los Angeles route had become so impractical that there was no reason to remain attached to it.

Rebooking was still far from easy. It worked well online, provided one had an internet connection. Our ship used Starlink. There was free Wi-Fi aboard, but it was essentially unusable; at perhaps three in the morning, with nobody else online, one might just manage to open the Google homepage. Paid access came in several tiers. We bought the most expensive one. It was not excellent, but it qualified as a functioning internet connection.

Then the circumstances changed. Because the flight was delayed and everyone needed to rearrange their travel, the ship opened internet access to all passengers. The result was simple: when everyone had internet, no one had internet. The expedition staff repeatedly announced that anyone who had already rebooked, or did not need to, should please stay offline and leave the bandwidth to those still trying.

At around ten that evening, once we knew the flight would not leave the next day, we began working through the changes. By roughly eleven, everything was done.

We postponed our itinerary by only one day, which was an aggressive gamble. Our thinking was that if we still could not fly the day after next, we would stop trying to predict events, wait until a departure became possible, and then pay to rebook everything at once. The larger problem was that if we could not fly the following day, our ship would have to return to Argentina. At that point, changing the date would no longer be the real challenge. How exactly does one change a flight departing Chile into one departing Argentina?

On the third day, we finally flew to Chile. Those of us already aboard the ship were in reasonably good spirits. Many of the passengers, especially the white-haired retirees, appeared entirely unconcerned; they would have been delighted to spend a few more days in Antarctica. The captain had even arranged an additional landing on our bonus day, which everyone appreciated.

The passengers waiting in Chile clearly had a different experience. Their expedition was scheduled immediately after ours—the itinerary I mentioned earlier that flew both ways from Chile. It was already a relatively short trip, and now two days had been removed. I had never imagined that flying in both directions could carry this particular risk.

One of the options we were told they were offered was to withdraw from the shortened expedition, receive a full refund, and receive roughly $1,000 in credit toward a future booking. It was better than nothing. A thousand dollars sounds substantial, but in many cases it would not even cover the airfare to and from Chile. The journey would have been for nothing, and the vacation days had still been spent.

The version I heard was that, out of more than 140 passengers, only four chose the refund. Everyone else continued with the shortened expedition. I do not know whether they found those missing two days too limiting, but I felt sorry for them.

All I could say was that we had been fortunate that itinerary was already sold out when we booked. Otherwise, I would have been among them. Sometimes luck works in strange ways.

A serious warning, then: anyone booking an Antarctica expedition that flies both ways should allow for the possibility that it may not operate as planned. Most disruptions may amount to only a few hours rather than the extraordinary delay we experienced, but a prolonged closure can create a logistical disaster.

We arrived in Puerto Natales at around ten in the morning and went through Chilean immigration there. The airport was very small and basic. Immigration processing certainly existed, but there was none of the enclosed inspection area one normally sees at an international airport.

After leaving the aircraft, we were taken as a group into a large room and formed a line for immigration. The line was too long to fit straight across the room, so it curled around on itself. This created a curious situation. The door leading into the terminal—that is, beyond immigration—did not appear to have anyone stationed directly beside it. It was simply an automatic door that opened when someone approached, and our looping queue passed directly in front of it.

From what I could see at that moment, it looked as though anyone in the group who felt so inclined could simply step through the automatic door without being stopped on the spot. It gave me the absurd impression that one could accidentally “immigrate illegally” without even leaving the room.

Which raised the more important question: why would anyone go to such lengths to enter Chile illegally? I do not know whether this airport handled any international flights other than charters from Antarctica. If it did not, and someone were determined enough to travel through Antarctica for that purpose, I hardly knew what to say.

Then again, passengers returning on this charter had already had their information checked and submitted by the ship’s operator. Under normal circumstances, everyone’s travel documents should have been reviewed well before arrival. Otherwise, we presumably would not have been allowed to board in Argentina in the first place…

Our onward flight departed at two that afternoon. Puerto Natales is tiny; the drive from the airport into town took about five minutes. We considered going in, then decided against it. A 26-inch checked suitcase was too cumbersome to drag around, and in an unfamiliar place where we did not speak the language, there was little reason to create extra complications for ourselves.

We then boarded the flight home without difficulty. At last, nothing else went wrong, and we made it safely home. Only then did our Antarctic journey feel truly complete.

That March, we went to Japan to see the cherry blossoms.

As usual with my travel stories, the visa came first. A Japanese visa was easy to obtain—at least from where I lived in the United States. The document requirements were clear, submission was straightforward, and approval was quick. In short, nothing went wrong, and the visa arrived soon afterward.

We booked two day tours from Tokyo. The original plan was Mount Fuji on the first day, a miscellaneous selection of nearby sights on the second, and a day on our own on the third.

By the time our flight arrived, it was already six in the evening. We had heard that the airport express was the sensible way into the city and that a taxi would be both expensive and slow in traffic. We bought tickets and managed to squeeze onto a train departing five minutes later.

After dropping our luggage at the hotel, we went looking for food. At a 24-hour convenience store, we picked up a random assortment of pastries, bread, and snacks. Back at the hotel, we tried them—and they were excellent. Japanese convenience-store pastries lived up to their reputation. By my own highly subjective standards, this casual selection could have trounced almost every pastry shop I had tried in the United States.

Then we went straight to sleep. I was getting too old to shrug off jet lag, and more importantly, the tour began at eight the next morning. To be safe, we had booked a hotel only a fifteen-minute walk from the meeting point. Unfortunately, that did nothing about having to wake up at seven.

The next morning brought the biggest mishap of the trip.

We left with plenty of time and, predictably, got slightly lost along the way. When we reached the meeting point, ten minutes remained before departure. Ten minutes should have been ample—until we saw the scene.

We had imagined one guide holding a small flag and checking names on a sheet of paper. Instead, there were twenty guides from the same company, some holding identical flags and others holding none at all, while what felt like ten thousand people crowded the edge of one cramped intersection.

That is barely an exaggeration. Moving through the crowd required actual squeezing, and bumping into people was unavoidable.

We spent ten minutes searching and still could not find our guide. The central problem was that we had no idea who the guide was: no contact details, no photograph, nothing. We showed our booking page to one of the other guides. He had never seen it and knew nothing about it.

Eight o’clock arrived, and the crowd began departing in groups. Even when only one guide remained, ours was nowhere to be found.

For no particular reason, I suddenly thought to check my email. There was a message from the previous evening containing the day’s detailed instructions—including the guide’s WeChat ID. I added him immediately. He told us the bus had left on schedule after waiting an extra two minutes. With more than fifty people aboard, it could hardly wait indefinitely.

And that was how we missed the day’s Mount Fuji tour.

It was not a disaster. We rebooked the identical tour for our third day and turned this one into our free day instead. First, however, we went back to the hotel and slept.

By noon, we were ready to eat and wander. We honestly had no destination in mind. I searched online for notable places nearby, marked all of them on the map, and set out.

Our first stop was Ueno Park.

At the time, we did not realize that this was a famous cherry-blossom destination; we knew only that it was a park where people went to see flowers. I later learned that it may be one of Tokyo’s best-known places for cherry blossoms, and that it also contains cultural institutions such as the Tokyo National Museum and Ueno Zoo. No wonder it was so crowded. The blossoms themselves were less impressive: very few had opened. We wandered around the park anyway.

Next came the center of the two-dimensional universe: Akihabara. It is Tokyo’s best-known concentration of anime, manga, and gaming culture, with specialty shops, themed cafés, and enormous electronics stores everywhere. Originally famous as an electronics district, it gradually became one of the world’s emblematic centers of otaku culture. That history inevitably reminded me of Akihabara’s reigning power broker in Steins;Gate, Faris NyanNyan.

We explored shop after shop, including a fair number devoted to material unsuitable for children. Akihabara truly was anime heaven.

That evening, we went to Ginza and wandered through several strikingly designed stores. One shop was supposedly famous above all for its elevator. We circled the area for ages and never found it.

That was the end of our first day.

On the second day, we joined the other tour and visited a few sights outside central Tokyo. Having learned from the previous morning, we added the guide on WeChat well in advance and found him without difficulty. The company used more than one departure point, and this one was just as crowded. Without that advance contact, we almost certainly would have failed again.

To be honest, the itinerary was not especially memorable. The exception was Kawagoe Hikawa Shrine. It is said to be particularly auspicious for finding a partner, and many people come to pray for romantic fortune. The shrine is best known for its sea-bream-shaped fortunes, which visitors fish up like tiny catches. They filled rack after rack—quite literally rows of them.

Nearby was Hikawacho, the neighborhood containing the shrine rather than a separate attraction in its own right. Most visitors come for the shrine and then walk along the Shingashi River, which is especially scenic during cherry-blossom season.

The photograph makes it easy to see why this is another popular place for cherry blossoms. Unfortunately, they still had not really opened.

That concluded the second day.

The third day brought the centerpiece of the trip: seeing Mount Fuji from a distance. Armed with the lessons of day one and the experience of day two, we reached the waiting area very early, met the guide before the crowds arrived, and settled into the bus.

Our guide was remarkably capable. He was Chinese, so Mandarin was naturally his first language. He worked as a guide in Japan, and his Japanese sounded fluent when he spoke with the driver. He had also spent years working in South Korea and spoke Korean fluently. Half the passengers that day were Chinese, half were Korean, and the driver was Japanese; we listened as he moved effortlessly among all three languages. Later, we encountered some lost Europeans, and he managed a little English as well. His English was not strong enough for a full conversation, however, so we stepped in to interpret. He said he planned to study seriously so that he could eventually lead European and American groups—Americans in particular, he added, came from a tipping culture and might mean more extra income.

We left on time. As the bus moved, the guide began lowering our expectations. Mount Fuji, he warned, was notoriously difficult to see. According to him, statistics suggested that on average it was reasonably visible in full on only about 140 days each year. He had checked the day’s forecast and was not optimistic, so we should not expect too much. He had even prepared small gifts to console the passengers if necessary.

Then we saw Mount Fuji from the bus.

He seemed almost surprised. We were extraordinarily lucky, he said. The previous two groups had not enjoyed anything close to this view; two days earlier, clouds had covered the sky all day and they had seen absolutely nothing.

Everyone was delighted and began taking photographs through the windows. The guide, I had to admit, was exceptionally good at expectation management.

Our first destination was Hakone, where we would see the torii standing in the water and ride a sightseeing pirate ship. Along the way, the guide explained that he had to compete for tickets every morning and simply take whatever sailing he could secure. On an unlucky day, he might get none at all, forcing the group to travel to the next stop by road. Most tour buses arrived within roughly the same window, he said, so success was largely a matter of luck. The expectation management had begun again.

There was, however, a little shortcut. Under the normal plan, the bus drove directly uphill to the parking area. The passengers stayed near the shrine while the guide sprinted downhill alone to buy the tickets. Whenever the buses arrived, the guides effectively staged an eight-hundred-meter final among themselves.

Procedures in Japan are generally followed fairly strictly, so that was usually how things worked. But if a guide had a good relationship with the driver, the driver might briefly stop at the small lot below the hill and let the guide out before continuing upward. That dramatically improved the odds of obtaining tickets. The lower lot was tiny and awkward for a bus, and the stop was outside the driver’s normal route, so the arrangement depended entirely on the guide’s rapport with the driver.

Our driver was willing to help. He stopped below, and the guide bought the tickets without having to sprint. Expectation management, relationship management—our guide appeared to excel at every form of management.

We first visited the shrine on the hill, then viewed the torii from land. The crowds were extraordinary. To take a photograph, I had to use my own body to block everyone else from the frame.

Then we boarded the pirate ship.

From the water, we saw the torii again from a different angle.

Next came Owakudani. The mountaintop was wrapped in fog and battered by fierce wind. We tried the famous black eggs afterward. Personally, I could detect no difference whatsoever between one of those and an ordinary boiled egg.

Then we had lunch. The guide ordered everything in advance, so the food was ready as soon as we arrived—a very efficient arrangement, although we paid for it ourselves. It was supposedly A3 wagyu. I certainly could not identify the grade, but the meat did melt in my mouth.

After lunch, we reached Oshino, an excellent place from which to view Mount Fuji.

We photographed the mountain from every angle.

There was also the cloud-wrapped version.

That concluded the tour. On the return journey that afternoon, the guide handed out the small gifts he had prepared after all. When he reached us, he quietly gave us an extra one to compensate for missing the first day’s departure. Still, he told us, missing that tour had been fortunate. The group two days earlier had seen nothing, while we had seen everything; Mount Fuji had truly cooperated with us. We had missed the tour, he said, but we had not missed what mattered.

That evening, we went to a restaurant said to serve eel in several different styles. We tried both Kansai-style and Kanto-style eel. We were told that the Kansai preparation was crisper and the Kanto version more tender. The Kansai dish we ate did indeed taste different from the soft eel I had encountered before.

With that, our time in Tokyo came to an end.

Our days in Osaka were remarkably busy. We explored not only Osaka itself but also the nearby cities of Kyoto, Nara, and Kobe—every one of them.

On the first day, we began in Kyoto.

Our first stop was Kiyomizu-dera.

The temple stands on a hillside, offering views across the city of Kyoto.

We then walked through nearby Ninenzaka and Sannenzaka, where we saw Hokan-ji’s famous five-story pagoda.

Nearby, we also found this distinctly Japanese Starbucks, where customers could sit on tatami while drinking coffee.

Then we reached the place I had most wanted to visit in Kyoto: Fushimi Inari Taisha. People online sometimes claim that it inspired the Grand Narukami Shrine in Genshin Impact, in which case there ought to have been Electroculi everywhere.

The resemblance to the game was difficult to ignore. I would not say the two looked exactly identical—only that there was practically no difference.

From there we continued to Nara and met its most famous creatures: the deer. After generations of exposure to tourists, Nara’s deer had lost all fear of people. If anything, they were the frightening ones. Hold food in your hand and a deer would reach over and eat it. Put the food in your bag and it would put its head into the bag and take it. More than once, we saw deer chasing people down the path. They were formidable.

Fortunately, we had no food in our hands.

We reached Todai-ji and finally shook off the herd behind us.

After walking around the temple, we wandered through a nearby park. There we found what may have been the finest cherry tree of the entire trip. What drifted through the air was not snow, but cherry blossoms.

And with that, our visit to Nara ended at remarkable speed.

On the second day, we went to Kobe. We began at Kobe Port Tower and took the elevator to the observation deck. Visitors could borrow various signs for photographs. One read “神戸ビーフ最高”—“Kobe beef is the best.” With my A0-level Japanese at the time, I somehow interpreted it as “Kobe’s tallest building.” I had thoroughly confused ビーフ, “beef,” with ビール, “beer.” Worse still, ビール does not mean building at all; that would be ビル. I had managed to be wrong twice in a single reading.

From the top, we photographed the panorama of Kobe Harbor.

Back at ground level, we stopped for a photograph at one of Kobe Harbor’s familiar landmarks. The area was crowded, so I used my usual method: wait for one group to leave, take the picture in the gap, and move on immediately.

At noon, we ate whatever we could find nearby. That had not been the plan: we entered a restaurant in Kobe specializing in Kobe beef, only to discover that this Kobe beef restaurant in Kobe had no Kobe beef. We were short on time, so a random lunch it was.

We then visited the Kitano Ijinkan district, a historic neighborhood on the slopes of Kitanocho in Kobe’s Chuo Ward, Hyogo Prefecture. After the Port of Kobe opened in 1868, many foreign residents settled in the area, leaving behind numerous Western-style houses from the Meiji and Taisho periods.

While waiting for our ride nearby, we found a small stall selling wagyu sushi. With my A0-level Japanese, conversation was out of the question; all I could do was point. It was spectacularly expensive. As I remember it, each piece worked out to more than ten US dollars, while the price in yen seemed to contain an alarming procession of zeros. The chef placed raw wagyu on sushi rice, then seared it with a blowtorch. As for the flavor, perhaps I simply lacked the palate to tell whether it was exceptional.

Next came Arima Onsen at the foot of Mount Rokko, home to the well-known Taiko footbath. I certainly was not getting in—the inconvenience was enough to deter me—but some of my companions were far more committed.

Nearby was also the Gososhi-an at Onsenji Temple, so we climbed up for a look.

That concluded our day in Kobe.

On the third day, we finally toured Osaka. We had been staying there for three days, and at last we were going to see the city itself. As one of Japan’s great food cities, Osaka demanded that eating be treated as a central part of sightseeing.

Over those days, we went through sukiyaki, sushi, gyudon, eel rice, and more.

At one meal, I encountered a remarkable hot pot. The pot was a sheet of paper.

It was an impressively sturdy sheet of thick paper. It sat over the induction cooker for more than an hour and survived repeated prodding with chopsticks without tearing. Had it failed, the result would presumably have been a major incident.

Beyond eating, we visited several of Osaka’s best-known landmarks, including Osaka Castle. Its main keep was visible from a considerable distance. We crossed the moat, wound our way through the grounds, and eventually arrived beneath the castle tower.

Admission required a ticket, and the line was enormous. While we waited, a staff member held up a QR code and explained that anyone buying online could skip the ticket line. We bought our tickets online and immediately bailed out of the queue.

From the tower, we could look down over Osaka Castle and out across the city.

We then walked through Osaka Castle Park. When all the cherry trees are in bloom, I imagine it must be an excellent place for hanami. Unfortunately, they had not fully opened yet.

We also checked off a few assorted sights around central Osaka. The subway helped, but the distances still involved plenty of walking, and by then we were tired. Eventually, we reached Namba Yasaka Shrine.

Getting there had been unexpectedly complicated. Osaka has several shrines with “Namba” somewhere in their names, and we walked straight to the wrong one. When the extravagant structure in the photograph was nowhere to be seen, I briefly assumed it had been demolished. Only later did I realize that we were simply at the wrong shrine.

With that, the final day came to an end.

For me, everything at that year’s World Finals finally went according to plan. Nothing went wrong from beginning to end—an outcome that had become surprisingly difficult to achieve.

As usual, the journey began with the visa. I was exempt, so I could skip that step entirely. I later heard that quite a few other people had trouble, not with the visa itself but with paying the fee. The website supposedly accepted credit cards online, yet each payment attempt was blocked by the card issuer’s fraud controls. Switching cards produced the same result. People eventually either found a card from a bank with unusually permissive controls or called customer service for help. In any case, it was tedious. I have no idea why the visa-payment site triggered so many alarms.

None of this had anything to do with me—or so I thought. Once I reached Baku, the problem came back to bite me. It was not specific to the visa site; it seemed to be a broader issue with Azerbaijani websites. More on that later.

I had learned my lesson in Egypt. Since I was making the trip, I intended to see the surrounding area. I arrived a day early, paid for the extra hotel night myself, and booked a day tour. I later realized that I had still been thinking too modestly. Someone else had arrived two weeks early and traveled through the nearby Caucasus—Azerbaijan, Georgia, and Armenia. To be honest, that struck me as somewhat risky, given that Azerbaijan and Armenia had still been at war only a few years earlier. By then, however, visiting each country separately at least appeared to present no particular problem.

Armenia provided another interesting footnote. Six months before Azerbaijan was officially announced as the host, Armenia had issued a notice saying it had submitted a bid for the 2025 World Finals. At the time there was almost no information online; searching Google for the 2025 venue mostly produced predictions that it would be Armenia. Azerbaijan ultimately got the event instead. Given the two countries’ recent history, one could not help wondering whether any of these developments were connected. I had no idea, but the sequence was certainly intriguing.

On my second day in Azerbaijan, I set out on the day tour. Our first stop was the Gobustan rock-art site, whose history reaches back thousands of years.

There I saw many unusual carvings.

There was also this image, which was fairly clearly not prehistoric.

We were told that snakes lived in the area, so the permitted paths were marked off with ropes. An unidentified green powder had also been scattered beside the paths, supposedly to repel them.

Next came the mud volcanoes. As the name suggests, these volcanoes erupt with mud.

The weather was intensely hot, yet the mud was cold. Our guide suggested touching it, so I did. Others in the group spread it over their arms and even their faces. Were they trying to turn a natural mud volcano into a facial treatment?

We then came to what is billed as the world’s first industrially drilled oil well, dating to 1846.

We also saw this enormous flag. I looked it up and discovered that it really had once held a world record. Somehow, it was a landmark in its own right. There was little wind that day, which made the flag difficult to photograph.

Next was Yanar Dag, the Burning Mountain, where natural flames burn continuously along the hillside. The mountain was, quite literally, on fire.

Then came Ateshgah, the Fire Temple, a religious site historically associated with fire-worship traditions. In the past, escaping natural gas kept flames burning there for years. According to our guide, the natural flame later went out, and the fire now burns on gas delivered through an underground pipe.

That concluded the day’s tour. We had managed to collect an impressive number of landmarks.

On the day before the contest, after all our work was complete, two Europeans and I decided to explore the city, with Baku’s Old City as the main destination. We began investigating how to get there, and the earlier payment problem came back to find me. We downloaded a local app and tried to buy some combination of transit card and metro tickets online. The credit card was declined immediately. Every attempt failed. Eventually we stopped trying and decided to go to the metro station and improvise.

How did one use the metro? None of us knew. According to my companions, working that out was part of the journey. We walked toward the station. Along the way, some local Azerbaijani students stopped us and asked how to improve at competitive programming. We offered a variety of familiar advice, all of which eventually reduced to the same conclusion: practice more.

Their uncertainty was understandable. New students always go through that stage. Codeforces now contains well over ten thousand problems even before Gym is counted. The scale alone can be discouraging.

At the metro station, we discovered that tickets could only be purchased with cash. We had none. A passerby saw the three of us looking thoroughly confused and gave us a metro card with exactly enough credit for two rides. We did not really understand what he said; he simply handed us the card.

We still needed two more fares. That meant finding an ATM outside and withdrawing the equivalent of roughly twenty dollars. At that amount, the debit-card fee may well have exceeded the money we withdrew.

We took the metro to Baku’s Old City and spent an hour exploring on foot.

Once we finished, it was time to decide how to return. The two Europeans thought the weather was pleasant and proposed walking back. So the three of us set out for the hotel. In my view it was extremely hot, the sun was fierce, and I had not applied sunscreen. They appeared entirely unconcerned.

Along the way, we passed several buildings with striking designs.

The most remarkable recent example, however, was the Heydar Aliyev Center beside the contest venue. By comparison, the venue itself hardly seemed worth photographing.

Contest day arrived without incident.

There was no one outside the venue, so I took the opportunity for a photograph.

The contest itself also concluded without incident. Congratulations to St. Petersburg State University, the only team to solve eleven problems, on winning the championship. Their ability to solve the problem designed to prevent an early sweep showed that the title was thoroughly deserved.

That problem had been in preparation since the previous year and was one of two intended to keep even the strongest teams busy until late in the contest. Before the 2024 event, we concluded that it was nowhere near ready and held it back. After another year of preparation and simplification, many of the more complex cases in its original form had been removed. As the problem author put it, “We have done everything we can to make this problem solvable.” Then someone solved it. One should never underestimate the strength of a World Finals team.

Another notable feature of that World Finals was that AI systems had applied to take part in an unofficial evaluation alongside the contest. The organizers provided OpenAI and Google DeepMind with separate judging machines so that each could work through the contest independently. What followed was decisive. Google DeepMind began extremely well and quickly solved ten problems, by which point the organizers were already becoming nervous. OpenAI then swept the entire problem set—AK’d the contest—and the comparison was no longer close. The organizers required both companies to wait until two weeks after the contest before publishing results and details. My guess was that they did not want the AI results to take attention away from the student competitors.

I later spoke with people from Google DeepMind. Given the level AI had reached, perhaps AI companies should no longer be applying for permission to participate. Instead, the organizers would need to provide a dedicated platform for AI entrants. How quickly the tables had turned.

The story continued a month after the contest, when we decided to hold a retrospective meeting. We had not held one even after the major crisis the previous year, so this meeting conveniently covered that as well. The central question was how we had managed to produce so many problems for ourselves. The conclusion was that more people should review the candidates during problem selection. We therefore decided to add members to the problem selection committee.

First, tourist clearly needed to join. His breadth of experience made him especially good at spotting issues—particularly if a similar problem had appeared in another contest, something he was more likely than anyone else to recognize. Most of the other judges rarely competed online.

One senior judge then suggested simply adding every judge from that year’s contest. Another pointed out that the discussion would become unmanageable when the final problem set had to be selected. The eventual decision was that everyone else could volunteer.

So I volunteered. It turned out that I was the only volunteer, which was mildly awkward.

Our journey through Oceania began with the difficult business of designing the itinerary. We had several constraints to satisfy.

First came New Zealand’s South Island. We did not feel like driving ourselves, so we joined a tour that ran between Queenstown and Christchurch once every five days. That immediately dictated the broad outline of the trip: either we went to New Zealand first and took the earlier departure, or visited Australia first and joined the tour five days later. We did not have separate New Zealand visas; under the policy that applied to us, our Australian visas allowed us to enter New Zealand provided we traveled there from Australia. That settled the matter.

The tour departed from Christchurch, which raised the next question: should we visit New Zealand’s North Island or South Island first? We found that flights from the South Island back to the United States generally required a connection on the North Island, while the North Island offered direct flights. South Island first, then, was the obvious choice.

We could now consider where in Australia we might fly to Christchurch from. Cairns was non-negotiable—we were going diving at the Great Barrier Reef. Cairns had no direct flight to Christchurch, however, so we would have to connect in either Melbourne or Sydney. In that case, why not stop and explore? Melbourne was noticeably cheaper, so we provisionally added it to the itinerary.

But how were we to get from the United States to Cairns? There was no direct flight there either; once again we had to connect in Sydney or Melbourne. A closer look revealed connection times so dreadful that they were unacceptable. So, once again: why not spend a day at the connection point? I compared the total airfare for Sydney, then Cairns, then Melbourne against the same route in reverse. The former was clearly cheaper and had much more sensible timing, so that became the plan.

You may find this hard to believe, but Melbourne was never part of our original plan at all.

And that, in summary, was how the itinerary came into being.

We left the United States on the evening of December 10, 2025. By the time we arrived it was already the 12th; December 11 had simply disappeared from my life.

For the fifteen-and-a-half-hour flight, we traveled in Premium Economy. My personal view is that most people who pay outright for Premium Economy are getting a poor bargain; it mainly makes sense as an upgrade. The difference from Economy is modest, the recline remains limited, and the fare is often more than twice as high. Yet when I checked the airline’s website, Premium Economy cost 70,000 points while Economy cost 87,000. It made no sense, but there it was.

So we booked Premium Economy. Only seats in the last row remained when we selected ours, and that was where the trouble began. The seats were close to the wall, further restricting how far they could recline. Anyone who has flown knows that aircraft seats are not exactly precision instruments. Their official recline is one thing; a sufficiently heavy passenger leaning back can sometimes persuade the mechanism to yield what feels like another ten degrees. Normally body weight can coax out a little extra angle. Against a wall in the last row, there was no such possibility. It was deeply uncomfortable. Lesson learned: I am never choosing the last row again.

In the end, we rested reasonably well—though on a flight that long, it was difficult not to. That afternoon, as planned, we visited Sydney’s well-known Taronga Zoo. Here was the zoo map.

At the zoo, it was another ordinary day of Fantastic Beasts and Where to Find Them.

There were also capybaras, now seemingly unavoidable internet favorites.

And koalas. We would see many more later at a zoo devoted specifically to them.

That brought the day to an end. We hurried back to the hotel to sleep and adjust to the time difference.

The next day, we visited the Sydney Opera House.

We joined an interior tour and wandered through much of the backstage area. The guide shared all manner of behind-the-scenes stories: the architect’s family drama, the passions and grievances surrounding the building, and a quiz for the group—was the only person ever to have climbed the Opera House Tom Cruise or Jackie Chan?

The next photograph shows one privilege of taking the interior tour: a concert hall, empty-auditorium edition.

Afterward, we had little else planned and a flight to catch that afternoon, so we walked through the nearby park. The scenery was quite lovely, and the park offered another distant view of the Sydney Opera House.

It was already evening when we reached Cairns. After checking into the hotel, we went straight back out to find dinner. This was unmistakably the tropics: the restaurants and casual open-air eateries lining the street reminded me strongly of Hainan. There was no danger of going hungry. Food was everywhere, places stayed open late, and the night market was lively.

The weather looked good when we woke the next morning.

That day we took a sightseeing flight over Cairns and its surroundings, first circling above the inner Great Barrier Reef and then flying over the rainforest and mountains inland.

That was our only scheduled activity, so the rest of the day became a leisurely walk around town and along the waterfront.

The third day brought the main event of the entire trip: diving at the Great Barrier Reef. The excursion included both snorkeling and scuba diving. To take photographs underwater, we had bought transparent, fully sealed phone pouches while walking around town the previous day. They were expensive. A quick check on Amazon suggested that ordering online would have saved roughly twenty percent. We no longer had that option, of course, and a twenty-percent premium for buying one on the spot was not outrageous. Still, anyone planning a similar trip should bring a pouch from home.

We set out early that morning in high spirits. The excursion included hotel pickup, and because we were worried about missing the vehicle, we went downstairs well ahead of time. Eventually a small van arrived and drove us to the nearby marina. Cairns truly is compact: we could have walked to the marina in less time than we spent waiting for the ride.

Once aboard, we signed several liability waivers and assumption-of-risk forms without even reading them—our cheerful little stack of “sign here in case everything goes wrong” paperwork. Then came a ninety-minute boat ride to the first site.

Into the water!

We had assumed that as long as the pouch kept the phone dry, we would be able to operate it underwater. That proved optimistic. The pouch did keep the water out, but we could not operate the phone at all. It was not a defect in the pouch; everything worked normally at the surface. Underwater, however, our touchscreens simply stopped responding. Only the phone’s physical buttons still worked. Fortunately, we had anticipated this possibility and looked up a workaround in advance: in camera mode, the volume button acts as the shutter. Every underwater photograph we took was made that way.

There was one crucial rule: do not press the power button. If that happened, the adventure was over. The phone would lock, and without a working touchscreen there was no way to unlock it. Even with no passcode, we could not swipe past the lock screen and return to the camera. The only solution was to surface, unlock the phone, and dive down again.

So we swam along, hammering the volume button. The Great Barrier Reef really was beautiful—almost dreamlike.

Snorkeling here revealed more than coral. There were plenty of animals as well, especially tropical fish.

After climbing out of the water, we realized that we appeared to have forgotten our towels. The pre-departure information had advised bringing them because none would be provided, but I had forgotten. We had booked the excursion months earlier and I had never looked at those instructions again. A careless mistake. Our only choice was the ancient art of drying oneself: sun and wind. In that Pacific weather, the technique worked remarkably fast. A little sunshine and sea breeze dried our skin almost at once; after lying on a sunny deck chair for a while, even our swimsuits were dry. I would still strongly recommend bringing a towel. This method is not kind to the skin.

Because we were not certified divers, our scuba dive was an introductory one led by an instructor. On this particular excursion, that meant going a little over ten meters down. There was little point going farther anyway; we had already reached the seabed. We had read online that a phone might be fine at around ten meters, but the instructor told us it could break under the pressure and advised us not to take it. After weighing the risk, we left it behind.

For both scuba diving and snorkeling, we were advised to wear the full-body protective suits supplied on the boat, reportedly to guard against stinging jellyfish. We had not understood that. We assumed the suits were only for scuba, so we wore none while snorkeling. Seeing so many people on the boat changing into them, we wondered whether that many passengers were really planning to dive. They were, of course, snorkelers. When it was finally time for my scuba dive, I had still not put one on, and the instructor fitted the tank onto me before I had a chance. Fortunately, no jellyfish stung me. I did, however, accidentally scrape my knee against the reef on the seabed because my swimming skills were so poor, breaking the skin. Back aboard, we applied every disinfectant in sight for fear of infection. The lesson was clear: wear the suit.

We returned to the marina that afternoon and were told a shuttle would take us back to the hotel—in thirty minutes. No, thank you. We left and walked instead. Having learned from the morning, I knew I could have walked to the hotel twice in the time it took to wait.

On the fourth day, we joined a day tour of several attractions around Cairns.

The Curtain Fig Tree.

Millaa Millaa Falls.

And Paronella Park, often claimed to have inspired Hayao Miyazaki’s Castle in the Sky.

That brought our time in Cairns to an end.

On our first day in Melbourne, we headed for the Great Ocean Road. This is where I must introduce the animal that left the deepest and most enduring impression on me there: the fly. The flies along the Great Ocean Road were everywhere. There was no escaping them. Wave a hand while walking and you were practically guaranteed to hit several. In theory, a creature as small as a fly should be difficult to spot outdoors from three meters away. Not here. They announced themselves freely. Many visitors simply wore masks, because opening one’s mouth to speak was an exceptionally dangerous act. One careless moment and you might receive an unexpected serving of fresh protein.

I do not know how much of the Great Ocean Road had this problem, but every attraction we visited did. My guess was that the damp coastal environment encouraged the flies, while the apparent lack of anyone controlling them allowed matters to reach this point. I had encountered something similar at Alcatraz near San Francisco, though this felt even worse to me. I would strongly recommend bringing a mask. Insect repellent did not seem particularly useful; there were simply too many flies for it to stop them all, and one could always find a few with no regard for their own survival. Walk carefully as well. Without glasses, a fly might go directly into your eye. One flew straight into my glasses.

Setting aside this spectacularly poor visitor experience, the Great Ocean Road did offer some fine scenery.

Our first stop was the Twelve Apostles. A photograph of this place appeared on the cover of an English textbook published by People’s Education Press in China, so visitors could often be seen holding the book in one hand and a camera in the other, lining up its cover with the landscape behind it. The result: it really was identical. What intrigued me most was where they had found those textbooks. Surely they had not carried them all the way from China? Then again, if they had come after reading a Xiaohongshu guide, perhaps they really had.

The coastal road was genuinely beautiful. Yet when I look at it now, my first thought is still: this is exactly the sort of environment in which flies would thrive.

We stopped at a restaurant more or less at random. Outside it, we happened upon several lively birds. They showed no fear of people whatsoever; presumably they had long since grown accustomed to us.

We then reached Split Point Lighthouse. We were told that excessive visitor numbers during the peak season had led to the site being closed, so all we could do was photograph it from a distance.

Finally, as the journey was nearly over, we arrived at the journey’s beginning. Had we spent the whole day doing the Great Ocean Road backward?

That concluded the first day. Back at the hotel, I went straight for the shower. After a full day among the flies, those clothes were not going anywhere near me again.

On the second day, we began with the Puffing Billy Railway, one of Melbourne’s best-known attractions. How should I put this? Judged purely as transportation, it was ancient, rough, and slow enough that few people would choose to rely on it. Judged as a classic heritage railway, however, perhaps age only makes it more desirable.

The ride itself was excellent. As the photograph above shows, when we rode it, passengers could sit along the edge of the carriage and extend their legs through the railings. There was obviously room for only so many people to do this in each carriage; roughly half had to sit inside. Whether you secured one of those places depended on when you boarded, or whether someone later offered to trade seats. The people in our carriage were considerate. No one occupied the prized edge for the entire journey of more than an hour without giving anyone else a turn.

Next came Maru Koala and Animal Park. As the name suggests, its defining feature was the chance to observe koalas at close range. Seeing them draped lazily over the branches settled the matter: they really are professional tree-dwelling idlers.

The park contained plenty of other animals as well. We encountered a peacock displaying its tail. My traveling companion put the phenomenon neatly: no matter how many times you have seen it, you still want to take another photograph.

The park also had a large contingent of Australia’s homegrown boxers: kangaroos, in several different varieties.

Capturing a large one and a small one in the same frame was no easy matter either.

That evening, we went to the Phillip Island Penguin Parade. “Penguins everywhere” came racing ashore from the sea. The quotation marks matter: there were plenty of penguins, but not quite enough to cover the landscape. I had already visited Antarctica and seen what penguins truly everywhere looked like. Compared with that, this was on an entirely different scale. The other people in our group were thrilled, probably because it was their first time seeing wild penguins. My own reaction was inevitably more subdued. I had, after all, already weathered rather larger seas—and larger crowds of penguins.

The photographs below were taken nearby during the day. When the penguins actually returned at night, it was too dark for my photographs to turn out well. Flash photography was understandably not allowed, so I captured nothing worth showing here.

And with that, our time in Melbourne came to a successful close.

Our journey across New Zealand’s South Island began in Christchurch. The tour was agreeably unpredictable. We did not feel like driving ourselves, so we booked a multi-day group trip and simply looked at whatever our guide chose to show us. With no driving to worry about, every hour could be spent watching the landscape pass by. The guide knew the region’s attractions remarkably well and often carried us into obscure corners in search of popular photo spots.

We began in the city with Christchurch Cathedral.

Next came the botanic gardens, whose formal gardens had a character of their own.

Then we left Christchurch and headed deep into the countryside. As the vehicle continued south, the pastoral scenery of the South Island began steadily raising its game. It is difficult to describe in words. My recommendation is to look at the photographs and supply the poetry yourself.

That evening, I took a photograph in the small town where we stayed—proof, if nothing else, that I had been there.

We joined a stargazing tour that night, leaving at eleven and not returning until one in the morning. The southern sky differs from the northern one. My knowledge of constellations was nowhere near sufficient to explain how, but the stars in the Southern Hemisphere did seem brighter.

According to the guide, the southern sky appears to contain more stars largely because the center of the Milky Way lies toward the southern celestial sky, where the stars are densest and the Milky Way brightest. For an ordinary observer, he said, this makes the Southern Hemisphere better for stargazing. We were fortunate to have a perfectly clear night. The previous evening had been covered in cloud, and every stargazing group had received a refund.

This was the sky that night, photographed with the guide’s DSLR. My phone was plainly not capable of it. The picture would be different every day—or, more accurately, every moment. The stars themselves did not change appreciably, but meteors crossed the sky frequently, appearing at random almost as though they were continually respawning. Take the photograph at another instant and it would never be quite the same.

The next day brought another full day among forests, mountains, and pastoral landscapes. We stopped at a base offering scenic flights over the glaciers, though we did not book one. In Alaska, we had already toured a glacier by helicopter, and that aircraft had even landed directly on the ice. We decided we could pass this time.

We had instead booked a later excursion on Tasman Lake, taking a boat across the glacial lake to see the glacier. More than fifty years ago, what is now Tasman Lake was still almost entirely glacier. Today the glacier’s terminus continues to retreat rapidly, reportedly by more than a hundred meters per year on average. It remains New Zealand’s longest glacier, but at the present rate, I suspect our generation may see it retreat from an immense valley glacier into little more than residual ice high in the mountains.

The photograph below shows the starting point for the lake excursion. Fifty years ago, this was still glacier; now there was no trace of it. When it comes to glacial loss, I am thoroughly pessimistic. One might stop Europeans from using air conditioning, or Californians from buying gasoline cars, but how does one stop technology companies from constructing AI data centers? And how does one stop human civilization from moving forward? Those things seem to have an appetite for energy unlike almost anything that came before.

I do not mean that human progress should be obstructed in an effort to prevent global warming. My view has always been that problems created by technological development can only be solved by continuing to develop technology; trying to turn history backward is not a viable answer. For landscapes like this one, however, all I can say is: see them while they remain.

Over the following two days, the guide took us to many more places.

First came fields of lupins, spreading seemingly everywhere.

Only when we approached them did I realize that lupins belong to the legume family. After the flowers fade, they really do produce strings of furry seed pods.

The guide then took us to a number of “famous” social-media photo spots. The quotation marks are there because I had never heard of them, though they appeared to be popular on Xiaohongshu. One was this mountain bungee site. Its setting could hardly have been better: mountains, water, and a cliff to jump from. Promotional material claimed it was the world’s first commercial bungee-jumping site. I do not know whether that was true, but that was the line. I hesitated. I had bungee-jumped before, so doing it here would not have been a first, and in the end I declined. Later, I regretted it a little. I should have gone. It was an auspicious setting: succeed and it was a fine place to jump; fail and it would become an exceptionally permanent resting place.

We also saw the Lone Tree. That is the name of the popular photo spot. As the photograph shows, one tree stands by itself in the water. Becoming an internet-famous tree is apparently easy: all it has to do is leave the group chat.

We saw the unusual sight of a two-colored lake, along with still more beautiful pastoral scenery.

After four days on the road, we finally arrived in Queenstown. Our journey across New Zealand’s South Island had reached a fitting conclusion.

For the final stop of our journey through Oceania, we reached New Zealand’s North Island. To be honest, our original plan was simply to enjoy the country’s pastoral scenery, and the South Island seemed sufficient. Yet every flight from the South Island back to the United States required a connection on the North Island, and the connection times were uniformly dreadful. Since we were going to be there anyway, we might as well…

We searched online for things to do on the North Island and discovered Hobbiton. It had served as a filming location for several movies in The Lord of the Rings series and looked well worth visiting.

I had seen every film in The Lord of the Rings series, including the later Hobbit films. I was not a devoted fan, however, and could no longer remember many of the classic scenes. That did not matter. No knowledge of the films was necessary; the village itself had enough character to justify the visit.

The first thing we encountered at the entrance was a life-size Gandalf. Many of the people waiting to enter stopped for a photograph with him.

The site organized guided tours in several languages. English tours were plainly the most frequent and could generally be booked at almost any time, while tours in other languages were harder to secure. Chinese tours were especially difficult: demand was high and departures were limited. We did manage to book one. Had we ended up on an English tour, the guide might have started making jokes about the films while we stood there understanding the words but none of the references.

The first sight upon entering the village was its sign.

Then we entered the village itself. Visitors could often be seen striking all manner of strange poses for photographs—for example, launching into an enormous leap on an otherwise unremarkable path. No great powers of deduction were needed to realize that they were recreating scenes from the films.

It was a thoroughly developed attraction, except that my phone had no signal at all and could only use the local Wi-Fi. My location-tagged WeChat Moments post very nearly failed to make it out of Hobbiton.

Afterward, we visited the Waitomo Glowworm Caves. A guide took us into the cave aboard a small boat, and overhead the rocky ceiling was covered with points of light from the glowworms. It was an unusual and memorable experience. The photographs, however, were another matter. The lights were so small that the results looked little different from pointing a camera at the night sky, and were simply not worth showing here. As an aside, these “glowworms” are not fireflies in the usual sense, but the luminous larvae of an insect.

That completed the day we had arranged around our Auckland connection. With it, our journey through Oceania came to an end.

Today I visited Miyou Miaomiaowu in Shanghai’s Putuo District for my first cosplay experience. It does not appear to be an official HoYoverse store, but its selection of HoYoverse costumes was extensive. It also carried plenty of popular characters from other companies.

I had booked online several weeks earlier, choosing both the studio set and the costume in advance. Today’s character was Zhongli from Genshin Impact.

The first step after I arrived was makeup. The makeup artist tucked all my hair into a wig cap and went to work. An hour and a half later, she was finally done. Full makeup really does take time.

Then I looked in the mirror—and the result was almost impossible to look at. I could vaguely see what she was working toward, but it clearly needed the costume to make any sense. On its own, the makeup looked profoundly strange: my face was ghostly pale, the eyeliner was dramatic, and there was even a touch of blush and lipstick. With all my hair hidden under the cap and none visible around my face, I looked like a screen portrayal of Li Lianying, the well-known Qing-dynasty court eunuch.

No photograph, no proof. It looked too awful to share.

Next came the colored contact lenses. My prescription is very strong, so I was surprised that they had lenses close to it in the right color. The shop was impressively well prepared.

Then it was time for the costume. I strongly recommend choosing a slightly larger size. Following the shop’s size chart, I had selected an outfit that came only in M and XL. My waist was exactly at the upper limit for M. Once I got there, however, the trousers decisively refused to fit. More precisely, I could just about squeeze into them with considerable effort. The problem was that any sudden movement—or simply sitting down—seemed likely to split the seam. At that point, who would be paying for the damaged costume?

So I left the trousers unbuttoned, which improved matters considerably. The top covered the waistband, so no one could tell.

Then came the photography. The photographer was equally professional. If I had no idea how to pose, he showed me exactly what to do and how to make it look suitably dramatic. I spent less time worrying about looking dramatic than about whether each dramatic pose might finally tear the trousers.

After the shoot, I had half an hour to explore on my own. Any unoccupied studio set was available for photographs, and the selection was quite varied.

Once the session ended, I could simply change and leave. I had no desire to go outside wearing the full Li Lianying look, however, so I removed the makeup there. The shop supplied makeup remover and every tool I might need. The trouble was that I had no idea how to use any of them. I simply scrubbed away, with enough determination that it felt as though I might take off a layer of skin.

Eventually my complexion seemed to have returned to normal, so I left. That evening at the hotel, I washed my face and discovered that the eyeliner along my waterline was still completely intact. I had not noticed it, but one wipe with a towel produced a black streak. Another painstaking round of washing followed.

Then came the photo editing. The shop’s packages included different numbers of professionally retouched images, but they all had one thing in common: a wait of at least two weeks.

The official service also did not create the special effects I wanted. I therefore looked online for someone else to edit the photographs, only to find that the paid retouchers I contacted did not make those effects either. In the end, I had to create them myself with AI. Fortunately, by then AI image editing was capable enough to produce fairly good results; otherwise, the effects would probably never have happened.

At the time, AI seemed very good at special effects but much less convincing at portrait retouching. I asked it to smooth my skin, slim my body, and lengthen my legs. It appeared to understand none of this: the edited result looked exactly like the original. So I hired a person to retouch the portrait instead. Once special effects were no longer part of the request, finding someone was easy.

That is how this first set emerged: AI effects followed by human portrait retouching. I thought the results were rather good.

I was still being naïve. Eventually the shop’s own retouched photographs arrived. One look was enough: these were formidable. The degree of retouching went far beyond what I had received from the freelancer I found online. The freelancer had done the paid job, met the basic requirements, and stopped there. The shop’s retoucher seemed to be working with genuine devotion to the cause.

Here are the results.

The retouching was so aggressive that my own mother might not have recognized me. At that intensity, cosplaying a female character next time would present no difficulty at all: beautification filters during the shoot, then more editing afterward.

To borrow—and thoroughly butcher—an old Chinese verse:

One photo polished, one photo refined; Side by side, can you tell which gender is mine?

I never actually entered Panama; I only changed planes in Panama City. Still, this was where my journey to Peru began.

The stopover is worth mentioning because something unexpectedly fortunate happened. I was flying Copa Airlines, one of several Latin American carriers that let passengers bid for an upgrade. You choose an amount within a suggested range and submit it without knowing what anyone else has offered. The upper end of Copa’s range puzzled me—it was higher than the price shown by the “upgrade now” button.

With little expectation of success, I entered the minimum bid. The original ticket had cost a little over $600, and I offered another $400 for the upgrade. Somehow, it cleared. On an earlier trip to Argentina, I had bid well above the minimum and still lost. This time, perhaps no one else on the flight was especially eager to spend the money.

I arrived in Lima that afternoon and went almost directly to a food-tasting tour. The idea was simple: sample a wide range of Peruvian specialties, including fresh tropical fruit and an assortment of unfamiliar snacks.

That was also my introduction to ceviche, one of Peru’s defining dishes. At the time, I knew little about it beyond the bowl in front of me: pale raw fish, sliced onion, a few green leaves, and a sharp citrus marinade. I later learned just how celebrated ceviche is. My own reaction was less enthusiastic. The acidity and raw onion were simply more intense than I enjoyed, and I did not think to take a photograph.

Next we visited a Chinese-Peruvian restaurant. In Peru, restaurants of this tradition are generally known as chifas. The cuisine grew from Chinese migration more than a century ago, and the name is commonly linked to the Chinese phrase chi fan—“to eat a meal”—adapted into local pronunciation.

The chef was not Chinese, but he handled the wok with confidence and prepared beef in a thick sauce. It reminded me of Panda Express. Compared with the Chinese cooking I knew, the beef seemed to have spent a little too long over the heat.

While moving through the city that afternoon, we also stopped at a well-known area for street art. This was the piece that stood out to me.

That evening I went to Juanito, one of Barranco’s most characteristic old bars. Juan Casusol founded it in 1937, and over time it became a gathering place for writers, artists, and the neighborhood’s bohemian community. Its exterior remains remarkably discreet, with barely a sign, and the Casusol family still runs it. The founder was known as Juanito—“little Juan,” using the affectionate Spanish diminutive.

Over the next several days, I joined a series of small group tours and saw a broad cross-section of Lima and its surroundings.

I began at the main square in the historic center, the Plaza de Armas, also known as the Plaza Mayor.

My visit coincided with Peru’s Independence Day celebrations and the approach of a presidential inauguration following the country’s five-year election cycle. The center of the square had been closed off, so I could only walk around its perimeter.

From there I visited the Cathedral of Lima. Construction began in 1535, when Francisco Pizarro, the Spanish conquistador who founded the colonial city, laid its first stone. His presence runs throughout the building. One story goes back to his second expedition, when his men were stranded on Gallo Island and many wanted to return to Panama. Pizarro drew a line in the sand; only thirteen men—the “Famous Thirteen”—crossed it and chose to continue south. According to the familiar retelling, his pitch was stark: follow him toward the possibility of wealth, or return north to the poverty they already knew.

I also passed through several smaller museums and collections. So many compact artifacts have been excavated in the region that some collections fill tier after tier of shelving. My favorite was this wonderfully abstract expression.

Museo Larco offered something entirely different. Its separate Galería Erótica (Erotic Gallery) presents erotic ceramics from ancient Peru, especially works associated with the Moche culture. The museum itself describes the gallery as a major collection devoted to sexuality and eroticism in ancient Peruvian art.

Uber made it easy to move between widely scattered parts of Lima without planning much around transportation. The driving, however, was an experience in itself. Most taxis had manual transmissions, and their drivers threaded through gaps and overtook with a precision that repeatedly looked like an imminent collision. Somehow, it all worked.

Peru’s tourism infrastructure also struck me as far more developed than the country’s broader level of development might suggest. Almost every established business I visited—even a modest stall with a permanent storefront—could produce a card terminal. Sometimes it had been unused long enough to need charging and a restart, but it was there. I barely needed cash outside informal street stalls. Tourist-site restrooms were similarly reliable: flushing toilets, paper, soap, and running water, not merely empty dispensers mounted on a wall. I had not found that level of consistency even on previous trips to Australia and New Zealand.

Food became another recurring part of these days. I am still not sure I could define “Peruvian cuisine” neatly, so I outsourced some of the decision-making. At restaurants, I photographed the entire menu and asked ChatGPT what to order. It was shamelessly convenient; by then, I could not even be bothered to study an English menu.

The dish most unlike anything I would encounter at home was roasted guinea pig. In much of the world it is a pet; in Peru it is dinner.

I also ordered a sampler of Peruvian specialties, with ceviche in the lower-right corner. The accompanying drink was equally unexpected: iced Americano mixed with passion-fruit juice. It sounded implausible, but there it was.

That brought my time in Lima to a close. Next came Cusco.

The most striking thing about the area around Cusco is the sheer number of archaeological sites. There were so many that, after a while, I could no longer reliably match every ruin to its name.

The Inca used terraces to stabilize steep slopes while expanding the amount of cultivable land. Around Cusco, terraces seem to cover every available mountainside. The region’s large temperature swings mean that elevation can change not only the temperature but, at times, the growing conditions themselves, allowing different crops to thrive at different levels. The circular terraces below were described to me as an experimental site used to learn what should be planted at each elevation.

Nearby, mineral-rich spring water feeds a vast complex of salt pans. The water is diverted through many levels of shallow terraces and left to evaporate in the sun. The site has a long history, but it is not simply a preserved relic: people were still actively harvesting salt when I visited.

The road between these sites offered its own memorable landscapes.

I joined several different full-day and half-day tours during this stretch of the journey. Beyond the sites themselves, the conversations gave me a broader sense of the country—and perhaps a clearer idea of why I travel in the first place.

One recurring subject was Peru’s long history of movement between continents. Spanish colonial rule is the obvious background, but several of my guides had much more recent European ties: a parent or grandparent from Europe, or a childhood spent there. International families seemed ordinary rather than exceptional. In my own experience, that felt different from the social environments I know in East Asia, including China, Japan, and South Korea, where cross-cultural marriage is more likely to be remarked upon.

I was equally impressed by how many languages people moved between. My sample was admittedly biased—guides are more likely than most people to be multilingual—but it extended beyond the tourism professionals. A shopkeeper in Cusco often spoke useful English in addition to Spanish, while many people in the region grew up speaking Quechua. Three languages could feel like a practical baseline. In China, fluent English alone is often considered an accomplishment; adding a third language draws real admiration.

The European travelers on my tours reinforced the point. One day, two Italians arrived speaking neither Spanish nor English, apparently trusting that Italian and Spanish were close enough to get them through Peru. When the guide struggled to communicate with them, another traveler simply stepped forward: he spoke both languages and could interpret. The problem disappeared almost immediately.

Not every guide, of course, was comfortable in English. A few had memorized the specialized vocabulary needed for their work but had difficulty building a complete sentence beyond it. They spoke in fragments, sometimes mixing in Spanish words. Because I know a little Spanish, I could recognize what was happening, but following the explanation was still difficult. A native English speaker might have filled in the gaps; I could not always do so. It was a humbling reminder that my own English still has room to improve.

With that, my time around Cusco came to an end. Machu Picchu was next.

This was the day I finally reached the centerpiece of the journey: Machu Picchu.

It is among the most difficult famous places I have ever visited—Antarctica may be the only destination that demanded more. Of the New Seven Wonders of the World, it must be one of the least straightforward to reach. First comes the long journey to South America, then a flight to Cusco. At more than 3,400 m above sea level, Cusco demands time to acclimatize. From there, I spent about two hours on the road to Urubamba in the Sacred Valley, boarded a train to Aguas Calientes, and rode for another hour and a half. The final choice was either a roughly two-and-a-half-hour climb or a twenty-minute bus ride up a genuinely unnerving series of switchbacks. Only then did the entrance appear. Few major attractions require this many stages.

Once I arrived, however, every stage felt worthwhile. My guide shared a great deal of history, but photographs convey the first impression better than another summary of facts.

Here is the wider view.

As the light moved, the color and texture of the entire city seemed to change with it.

My ticket was for Circuit 3, which descends into the urban sector but does not include the highest panoramic overlooks. Circuit 2 is generally considered the best balance: elevated exterior views as well as a closer look inside the site. It is also the first to sell out. If Circuit 2 matters to you, booking six months ahead is sensible; three months was not enough for me. Machu Picchu has firmly joined the small club of places that require half a year of advance planning.

There is also an in-person option. The ticket office in Aguas Calientes releases 1,000 tickets each day for the following days, but in high season even the next day’s allocation may already be gone. That morning my guide opened an app: tomorrow was sold out, while the day after still had about half its spaces. He explained that many buyers were Peruvians and visitors from neighboring countries traveling during school holidays. A family might decide on Machu Picchu, arrive to buy whatever date remained, spend the intervening days around Cusco, and return when their entry time came.

The city is inseparable from the mountain beneath it. In places, uncut bedrock supports the structures; elsewhere, the natural rock itself becomes part of a wall or platform.

A few more views show how completely the two are joined.

Sun protection is essential, and insect repellent is nearly as important. My guide wore gloves through the heat, which seemed odd until mosquitoes left several bites across my hands. Then the gloves made perfect sense.

There is one hotel at the top, in an extraordinary position beside the site. A room was roughly US$2,200 per night. From its location, it seemed entirely possible that opening the curtains would reveal Machu Picchu itself—a reminder of just how wide the range of travel can be when cost is no object.

My guide also told me that a large monolith once stood in Machu Picchu’s main plaza. According to his story, it was removed to make room for a helicopter carrying the king of Spain, then reinstalled after the visit. It was removed again for another visiting Latin American leader, damaged in the process, and could not be put back. The story ended on a distinctly awkward note.

On the final day of the journey, I explored the area around Aguas Calientes—less by choice than by necessity.

The reason was my three-star hotel, Flower’s House MachuPicchu, which suffered from several serious problems.

First, there was effectively no internet. Each floor had its own Wi-Fi network, except the fifth floor, where I was staying. The fourth- and sixth-floor signals were strong and used the same password, so connecting was easy. Getting online was another matter: Google’s home page took nearly thirty seconds to load, and most other sites were hopeless. I went downstairs and told the front desk that the fifth floor had no Wi-Fi. The receptionist quietly turned off mobile data on her phone before checking the network—strong evidence that she already knew exactly how unusable the hotel’s connection was.

Second, there was no cold water. I have stayed in plenty of hotels where the hot water failed; a broken heater is familiar enough. Cold water failing was new. During the day I had only washed my hands, using whatever cool water remained in the pipes, so I did not notice. That evening, after the tap ran for thirty seconds, the water became painfully hot. The receptionist appeared to know about this problem too. Some repair work required the cold-water line to be shut off regularly, she said, and it would return in ten minutes. It did, briefly. By the middle of the night, the cold water was gone again. Washing my hands became a race against the rising temperature.

Finally, there was the noise. The aging windows would not close properly, and sound insulation was essentially nonexistent. The hotel stood near the railway station, so the whistle of the first train at five in the morning marked the end of sleep. Earplugs softened it somewhat. They were not optional.

Taken together, the lack of internet and reliable water made spending the day in the room impossible. Under better circumstances, I might simply have rested. Instead, I set out for places my guide had recommended the day before. ChatGPT had suggested other sights, but the guide pointed out that one involved a three-hour walk each way. I agreed that was more than I wanted.

I first headed northeast toward a waterfall, passing the open-air Machu Picchu Hot Springs. From the trail above, I could see the entire complex. Water—whether genuinely thermal or not, I could not tell—had been directed into pools of roughly 10 square meters. The surface was clear; the bottom was not visible. Towels were not provided. Unless soaking in hot springs is a personal passion, I would not consider this an essential stop.

About ten minutes farther uphill was the first waterfall, Cataratas de Aguas Calientes. This was a developed attraction, with an entrance shared with the hot springs and admission payable by cash or card. Wooden benches appeared regularly along the trail, making the climb pleasantly manageable.

After descending, I set out for a second destination, the Allcamayo Waterfalls. This trail was almost entirely undeveloped. The first fifteen minutes climbed steeply over uneven stone to a small refreshment stand. There was nowhere to sit along the way; resting meant stopping in place and leaning on my legs. By the time I reached the stand, I was exhausted. I bought a ticket—cash and cards were both accepted—and continued for another five minutes to the first supposed waterfall. My immediate thought was: This counts as a waterfall?

Less than ten minutes farther in, I reached the second waterfall. This one looked considerably more deserving of the name.

The route runs through dense, largely unmanaged forest, and the footing is difficult. An injury—especially a twisted ankle—would become a serious problem very quickly. Insect repellent is also strongly advisable. Halfway in, an enormous unidentified bee or wasp began following me. It stayed with me all the way to the waterfall and most of the way back, disappearing only as I approached the edge of the forest. I would have preferred not to acquire a winged escort.

Unless hiking itself is the goal, I would probably skip this second waterfall. Compared with the first, the physical effort was much greater than the reward. By the time I emerged, my clothes were nearly soaked through with sweat.

From there I walked to the Mariposario of Machu Picchu, a butterfly sanctuary below the mountain. Walking was not a special decision: under ordinary circumstances, Aguas Calientes has almost no road traffic. Vehicles are largely reserved for deliveries and specific commercial uses, including the buses that carry visitors up to Machu Picchu.

The sanctuary held a large number of butterflies. The displays promised many varieties, although one species seemed to dominate during my visit.

At the very end, I took one hazy photograph looking up toward Machu Picchu from below.

With that, the journey was complete.