The is a railway line that runs through Tokyo and Chiba Prefecture, Japan. Part of the East Japan Railway Company (JR East) network, the line operates on separate tracks along the right-of-way of the Chūō Main Line (Chūō Line (Rapid)) and Sōbu Main Line (Sōbu Line (Rapid)), providing service between Mitaka Station in the cities of Mitaka and Musashino and Chiba Station in Chiba. The term distinguishes local trains on the Chūō-Sōbu line from rapid service trains running on the Chūō Main Line between Mitaka and and on the Sōbu Main Line between and Chiba. Service patterns Chūō-Sōbu Line Regularly, trains terminate at Chiba or Tsudanuma at the east side, and terminate at Nakano or Mitaka at the west side All trains stop at every station. For station information on the parallel rapid/express lines, see the Chūō Line (Rapid) and Sōbu Line (Rapid) articles. Tōzai Line through service All through service trains enter the Tōzai Line at either Nakano, or Nishi-Funabashi. These trains operate within the following routes: Mitaka – Nakano – (Tōzai Line) – Nishi-Funabashi – Tsudanuma (weekday mornings/evenings only) Nakano – (Tōzai Line) – Nishi-Funabashi – Tsudanuma (weekday mornings/evenings only) Mitaka – Nakano – (Tōzai Line) – Nishi-Funabashi Mitaka – Nakano – (Tōzai Line) – Nishi-Funabashi – (Tōyō Rapid Railway Line) – Tōyō-Katsutadai Limited express Certain limited express and seasonal trains run through, or stop at stations on this line. For information on the Shinjuku Wakashio and the Shinjuku Sazanami that make stops on the Chūō-Sōbu Line at , see their respective articles. Former Early morning / Late night At around 9 -10pm, a few westbound trains headed beyond Mitaka onto the Chūō Line (Rapid), with some terminating at Musashi-Koganei, and the others at Tachikawa. The other trains during the hour operated regularly. At around 4 - 6am and 11pm - 1am, Chūō-Sōbu Line services were divided at Ochanomizu Station, into two sections. At the western section (Mitaka – Ochanomizu), Chūō Line (Rapid) trains ran through the Chūō-Sōbu Line tracks between and , with services serving between and as far as , or even Ōme, which stops at all stations. At the eastern section (Ochanomizu – Chiba), local trains operated and terminated at the two ends of the section. This service pattern last operated on 13 March 2020. To prepare for the eventual installation of platform doors on Chūō-Sōbu Line platforms and the future addition of Green Cars