The Uchibō Line (内房線) is a railway line operated by the East Japan Railway Company (JR East) adjacent to Tokyo Bay, paralleling the western (i.e., inner) shore of the Bōsō Peninsula. It connects Soga Station in the city of Chiba to Awa-Kamogawa Station in the city of Kamogawa, passing through the municipalities of Chiba, Ichihara, Sodegaura, Kisarazu, Kimitsu, Futtsu, Kyonan, Tateyama, and Minamibōsō. The line is connected at both ends to the Sotobō Line. The name of the Uchibō Line in the Japanese language is formed from two kanji characters. The first,, means "inner" and the second, is the first character of the Bōsō. The name of the line thus refers to its location along the inner part of the Bōsō Peninsula in relation to the Tokyo Metropolitan Area, as opposed to the Sotobō Line, "outer Bōsō" which is on the opposite side of the peninsula. South of Kimitsu is single track, and north of Kimitsu is double track.

Station list

Notes:

Operation

The Uchibō Line operates local service with trains generally originating and terminating at Chiba Station. Trains headed directly for Tokyo Station merge with the Sotobō Line between Soga and Chiba Stations, and with the Sōbu Main Line between Chiba and Tokyo, while express and commuter trains merge with the Keiyō Line from Soga station.

Local trains

Daytime local service from Chiba to Kisarazu and Kimitsu (sometimes to Kazusa-Minato) is provided by around 2 round trips per hour. In addition, 1 round trip per hour runs from Kisarazu to Awa-Kamogawa (and to Kazusa-Ichinomiya through the Sotobō Line).

Keiyō Line through service

Keiyō Line Local, Rapid, and Commuter Rapid trains operate through services on the Uchibō Line between Soga and Kimitsu. In the morning, there are three inbound Rapid and Commuter Rapid trains, and in the evening, there are five outbound Rapid and Commuter Rapid trains and two inbound Local trains. On weekends and holidays, Rapid trains replace the Commuter Rapid trains. One of the inbound morning trains originates from Kazusa-Minato.

Yokosuka Line—Sōbu Line Rapid through service

Trains leaving north from Kimitsu connect directly to the Sōbu Line (Rapid), with some continuing onto the Yokosuka Line. Since the October 2004 timetable revision, all trains now stop at Nagaura and Sodegaura stations.

Limited express trains

The limited express train Sazanami runs from Tokyo Station to Kimitsu (and Tateyama station during busy periods). The limited express View Sazanami formerly ran on the Uchibō Line as well, but it was merged with the Sazanami following the timetable revision on December 10, 2005. The limited express Shinjuku Sazanami runs from Shinjuku to Tateyama on weekends and during peak seasons.

Rolling stock

Local service Keiyō Line through service Yokosuka Line—Sōbu Line Rapid through service Sazanami and Shinjuku Sazanami Limited Express

History

The Uchibō line began operation in 1912, and was originally known as the Kisarazu Line (木更津線). It operated from Soga Station to Anegasaki Station in Ichihara. Several extensions were built over the next few years, and in 1919 it reached Awa-Hōjō (present day Tateyama). At this time it was renamed the Hōjō Line (北条線). By 1925 it had been extended to its present-day terminus, Awa-Kamogawa Station. In 1929, the Hōjō Line was incorporated into the Bōsō Line. However, in 1933, the original section between Soga and Awa-Kamogawa Stations again became its own line, this time renamed the Bōsō West Line (房総西線), and in 1972 it received its current name. The Soga - Kimitsu section was duplicated between 1964 and 1971, and the entire line was electrified between 1968 and 1971. Individual section dates as given in the Timeline section below.

Timeline