The usual suspects:

Czechoslovakia in 1979 with parents and grandparents. We came to witness a manhunt on the border and Pilzen seemed very dark and Kafkaesque, that's about all I can remember.

East Germany in spring 1989 on a school trip. Depressing country, East Berlin was surely competing with Pyongyang and Moscow for the "ugliest city of the world" title back then. Radeberger Pils was splendid, however.