If you went to this European capital that existed only from 1949 to 1990, you'd definitely entered the "red zone"
[DOC] [TLE] Free Flashcards about EUROPE - StudyStack [PAR] IF YOU WENT TO THIS EUROPEAN CAPITAL THAT EXISTED ONLY FROM 
1949 TO 1990, YOU'D DEFINITELY ENTERED THE "RED ZONE", EAST BERLIN
.