Nambu Line - History

History

The private Nambu Railway opened the line in five phases between 1927 and 1930 (freight branches are omitted):

• March 27, 1927: Kawasaki – Noborito
• November 1, 1927: Noborito – Ōmaru (near Minami-Tama)
• December 11, 1928: Ōmaru – Bubaigawara (then called Yashikibun)
• December 11, 1929: Bubaigawara – Tachikawa
• March 25, 1930: Shitte – Hama-Kawasaki

Passenger trains used electric multiple units from the beginning. Major freight was initially gravel from the Tama River. When the railway reached Tachikawa and made connection with the Ōme Electric Railway, limestone became one of main freight. The railway was controlled by Asano zaibatsu, which was enabled by the railway to transport limestone from its own quarry in Western Tokyo to its cement plant in Kawasaki without using the government railways.

On April 1, 1944, the railway was forcibly purchased by the imperial government and became the Nambu Line of Japanese Government Railways. After the end of World War II, there were several movements to denationalize the line, but the line had been a part of the Japanese National Railways until its privatization in 1987.

The postwar sprawl of the Tokyo urban area turned the most of the farmlands along the Nambu Line into residential areas and multiplied the passenger traffic on the line. On the other hand, freight traffic has been reduced after the opening of the Musashino Line in parallel to the Nambu Line in 1976 and the discontinuance of the limestone freight in 1998, except for the Nambu Branchline, which is a part of main freight route.

Rapid services between Kawasaki and Noborito with stops at Musashi-Kosugi and Musashi-Mizonokuchi started on December 15, 1969, but were discontinued by the timetable revision on October 2, 1978. After 33 years, rapid services between Kawasaki and Tachikawa with more stops started on April 9, 2011, postponed from originally scheduled March 12 due to the earthquake in Tōhoku on March 11.