Closed city

A closed city or closed town is a settlement where travel or residency restrictions are applied. Historically, the construction of closed cities became increasingly common in the Soviet Union during the Cold War.^[1] Since the dissolution of the Soviet Union in 1991, they remain widespread in Russia and some of the other post-Soviet countries. In modern Russia the closed cities are designated as "closed administrative–territorial formations" (ZATO; Russian: закрытые административно–территориальные образования [ЗАТО], PRON. zakrýtïe administratívno–territoriál'nïe obrazovániya).