The is an railway line in the western suburbs of Tokyo operated by the private railway operator Seibu Railway. The line connects Musashi-Sakai Station on the Chūō Main Line with Koremasa Station along the Tama River. The line has only six stations and is not connected to any other part of the Seibu Railway system. The only connection to any other rail line is a rarely used maintenance connection to the JR East Chūō Main Line (just west of ) that is used to transfer trains requiring inspection or major repairs to Seibu's Musashigaoka Vehicle Inspection and Repair Shop.
The Tamagawa Line is single-track: trains traveling in opposite directions pass each other as necessary at the stations, which are double-track. , during 12-minute frequency trains pass at and , and during 20-minute frequency trains pass at only.
Although the line is short, it provides access to the Tokyo University of Foreign Studies, the Tokyo Racecourse, the Ajinomoto Stadium, the Tokyo Metropolitan Police Department police school, many cemeteries (including Tokyo's largest, Tama Cemetery), the American School in Japan, and the Tama River.
Services
All services on the Seibu Tamagawa Line are Local trains, stopping at all stations.
, trains operate every 12 minutes between 06:30 and 22:00 every day, and approximately every 20 minutes in the early morning and late at night.
Running time is 12 minutes towards Koremasa and 14 minutes towards Musashi-Sakai. The line was extended to Koremasa on 20 June 1922.