Shinjuku (Japanese: 新宿区, Hepburn: Shinjuku-ku; IPA: [ɕiɲdʑɯkɯ] ), officially called Shinjuku City, is one of the 23 special wards of Tokyo. It is located to the west of the Japanese capital.
Since the end of World War II, Shinjuku has become a major secondary center of Tokyo (fukutoshin), rivaling the original city center in Marunouchi. Today, it is a major commercial and administrative center, housing the busiest railway station in the world (Shinjuku Station) as well as the Tokyo Metropolitan Government Building, the administrative center of the Tokyo Metropolitan Government.