One year later than planned, I finally managed to visit Ukraine and now I can answer my own question.
Will I be admitted to the country?
I entered Ukraine by bicycle from Slovakia. The whole procedure took only minutes (in both directions). Officials on both sides were completely unsurprised by my presence. No one asked me a single question about the purpose of my trip. They just examined my passport and checked my backpack for alcohol and cigarettes (I carried none). I had a travel insurance from a Ukrainian insurance company, covering also some war-related risks for non-combatants. Anyway, I wasn't asked to show any proof of it. Also no one cared about any proof of Covid insurance.
Are trains in the west of Ukraine reliable?
I took a commuter train ("elektrichka") from Velikyi Bereznyi to Syanki on the northern side of the Uzhok Pass. Apart from the run-down state of the train, all was well, the train arrived and departed on time. However, even though I started my journey at a relatively big station where also long-distance trains stop, they only accepted payments for tickets in UAH. No Euros, no cards. Fortunately, there were several banks and ATMs in that little town, so not a big problem. Ticket for long-distance trains in Ukraine can be bought also online (web or various apps), but for commuter trains it's not possible.
Will I be viewed as a nuisance?
I spent a lot of time in the mountainous area close to the borders with Poland and Slovakia, I'm a military-aged male and I stood out because I wore outdoor clothes and rode a mountain bike (not so typical for the area, where elderly people ride old rusty bicycles). As a result, I got stopped about ten times a day by officers of the police and the DPSU (border guard). For example, when I was waiting for a train on a platform, a man just appeared out of nowhere, flashed his ID and wanted to know who I was. On another occasion, I stopped my bike by the roadside to drink some water and suddenly a car pulled over and another man did the same thing. I also passed through several permanent checkpoints. Some have existed there since the Soviet times (but now the security is tightened), some are newly created. None of the officers was rude to me, all of them were very polite. None of them was trying to extort a bribe. When they saw I was a Westerner (and not a Russian, or a Ukrainian trying to escape being drafted to the army), they just took photographs of my passport's data page and of the entry stamp and let me continue. I once strayed too close to the border (because that's where a hiking trail led me) and they checked my passport, talked with a superior over the phone, and then politely asked me to leave, explaining that now during the war there is a buffer zone of 5 km from the border, in which no one is allowed to be without a special clearance.
On the contrary, in Uzhhorod (a big city), I saw no permanent checkpoints and no one stopped me. Ordinary people were always very friendly and talkative, none of them made me feel like an unwanted intruder.
Few more points:
- It's now more than two years since the Russian invasion to Ukraine started and the war has unfortunately become a new normal in Ukraine. If I had made the same trip in 2022, the officers could have reacted far more hysterically.
- I don't speak Ukrainian or Russian, but I speak Slovak language, which is not really mutually intelligible with Ukrainian, but it's close enough to communicate basic things. I also learned a few important Ukrainian words in advance. English won't help at all, as won't any non-Slavic foreign language. Modern technologies can help to bridge the language gap, but I wouldn't like to depend on them.
- If you lose your passport, you could end up in a big trouble (possibly a few days' detention), because you might not even be able to reach your consulate without being stopped by a law enforcement officer.
- Even though I can't recommend Ukraine as a safe tourist destination, the Zakarpattia Region is not life-threatening either (as of the time of writing). By far the biggest dangers were reckless drivers, aggressive dogs in little villages and wildlife (brown bears).
- Finally a pro tip: it helps to break ice if one greets young people with Slava Ukraini! ("Glory to Ukraine!") and elderly people with Slava Isusu Christu ("Glory Be to Jesus Christ"). :-)