History
Shinjuku-sanchōme Station is a three-line underground interchange in Shinjuku, Tokyo, jointly operated by Tokyo Metro and Toei Subway. The Marunouchi Line platforms opened first on 15 March 1959 under the Teito Rapid Transit Authority, followed by the Toei Shinjuku Line platforms on 16 March 1980 and the Tokyo Metro Fukutoshin Line platforms on 14 June 2008. The Marunouchi Line facilities passed to Tokyo Metro at the TRTA's privatisation in 2004. Each line is served by its own island platform, with Marunouchi and Fukutoshin interlinked while the Toei Shinjuku Line requires passing through both operators' ticket gates. An underground passage called the Metro Promenade links the complex to Shinjuku Station, with a parallel passage beneath Kōshū Kaidō added in 2012.
History summarized from Japanese & English Wikipedia · last reviewed 2026-05-18.
Notes
The Tokyo Metro and Toei platforms are not within a single fare-paid zone—transferring from the Toei Shinjuku Line to the Marunouchi or Fukutoshin Line requires passing through both operators' ticket barriers on the main concourse.