Sotobō Line


The Sotobō Line is a railway line in Japan operated by the East Japan [Railway Company] adjacent to the Pacific Ocean, on the eastern side of the Bōsō Peninsula. It connects Chiba Station in Chiba to Awa-Kamogawa Station in Kamogawa, passing through Ōamishirasato, Mobara, Chōsei, Ichinomiya, Isumi, Onjuku, and Katsuura. The line is connected to the Uchibō Line at both ends. South of Kazusa-Ichinomiya is single track, and north of Kazusa-Ichinomiya is double track.

Services

In addition to local services, limited express and Rapid services run on this line.
  • Limited Express Wakashio
  • Rapid
  • * – – Tokyo – – Soga –
  • *Tokyo – – Soga – – Kazusa-Ichinomiya
  • **Commuter Rapid services through to/from the Keiyō Line also used to operate, but they have been discontinued as of 16 March 2024.

Station list

; Legend
  • ● : All trains stop
  • : Some trains stop
  • | : All trains pass
; Notes

Rolling stock

Local service
Keiyō Line through service
Between and :
Sōbu Line through service
Between and :
Wakashio ''and Shinjuku Wakashio'' Limited Express

Former rolling stock

History

The Boso Railway opened the Chiba to Oami section in 1896, extending the line to Kazusa-Ichinomiya the following year and to Ohara in 1899. The company was nationalised in 1907. The extension to Katsuura opened in 1913, to Kazusa-Okitsu in 1927, and Awa-Kamogawa in 1929.
A new tunnel and associated deviation was opened at Toke in 1954 to improve the loading gauge of the line. The Chiba to Soga section was double-tracked between 1960 and 1963, extended to Nagata between 1972 and 1974, with CTC signalling being commissioned between Soga and Awa-Kamogawa in 1974. The line to Kazusa-Ichinomiya was double-tracked between 1980 and 1986, with the Onjuku to Katsuura section double-tracked in 1995, and the Torami to Chojamachi section the following year. The entire line was electrified in 1968, and freight services ceased between 1982 and 1987.

Former connecting lines

  • Mobara Station: The Mobara Town Council operated a, gauge handcar line to Tai Muko between 1909 and 1924. The council then decided to build a railway to connect to the Kominato Line. of gauge line was opened as far as Okuno between 1930 and 1933, the first following the handcar line alignment. Poor patronage and economic circumstances led to the line being closed in 1939.
  • Ohara Station: The Chiba Prefectural Government opened a, gauge handcar line to Otaki in 1912. A railcar was converted to petrol engine power in 1922. The line closed in 1927 to allow for the construction of the Isumi Line, which opened on the same alignment in 1930.

Accidents

On 8 May 2020, at 3:55 pm, the front carriage of a local service derailed between Awa-Kamogawa and Awa-Amatsu stations. Around 20 passengers and crew were on board the train when it derailed. One person was taken to a hospital.