When we created this page, Crimea was a part of Ukraine. And while we do not comment on political developments (you may check the Wikipedia page for more details) we were not amused. The problem is the hierarchical structure of the website. If you look at the URL you will see the two letter countrycode in the url. But this region page and all listed sites now belong to a different country which changes the url. And as a result the links in search engines are outdated as long as it takes to recrawl the site, which might take months. That's normally not a problem, as countries do not tend to stand up and walk away. Normally.
However, after almost 15 years we had to finally accept the reality even if we are not happy about it. We have moved the Crimea and all of its underground sights to the Russian Federation.