The places are officially known as "closed administrative-territorial formations" (закрытые административно-территориальные образования, zakrytye administrativno-territorial'nye obrazovaniya, or ЗАТО ZATO for short) in Russia and were called that in the former USSR. The system covered a lot of places including Sakhalin Island, cities, factories, military basses, gulags and the Mirny Diamond Mine in Yakutia.