Japan contains Tokyo.
Municipalities of Japan . There are four types of municipalities in Japan : cities , towns , villages and special wards ( the ku of Tokyo ) . Tokyo ( [ toːkjoː ] , [ langˈtoʊki.oʊ ] ) , officially Tokyo Metropolis , is the capital of Japan and one of its 47 prefectures . The metropolitan government also administers 39 municipalities in the western part of the prefecture and the two outlying island chains .