History
The line opened as a one-stop single-track spur from Chōfu to Keiō-Tamagawa on 1 June 1916, electrified at 600 V DC, and was double-tracked on 1 April 1924. On 1 May 1937, Tamagawara was renamed Keiō-Tamagawa, and on 4 August 1963, the voltage was increased to 1,500 V DC. The line was extended (all extensions were electrified dual track) on 1 April 1971, to Keiō-Yomiuri-Land. Subsequent extensions brought the line to Keiō-Tama-Center (18 October 1974), Minami-Ōsawa (22 May 1988) and Hashimoto (30 March 1990). Tamasakai station opened on 6 April 1991. In 2012, the Chofu to Keiō-Tamagawa section was relocated underground. Station numbering was introduced on 22 February 2013. ==See also==