First service 10 March 1975 Former operator(s) JNR | Current operator(s) JR East | |
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The Shiosai (しおさい) is a limited express train service in Japan operated by East Japan Railway Company (JR East). It runs from Tokyo and Shinjuku to Chōshi on the Boso Peninsula in Chiba Prefecture.
Contents
Station stops
Shiosai services operate over the Sōbu Main Line, stopping at the stations listed below. Some services operate as "Local" all-stations services between Narutō and Chōshi.
Tokyo - Kinshichō - Chiba - Sakura - Yachimata - Narutō - Yokoshiba - Yōkaichiba - Asahi - Iioka - Chōshi
Rolling stock
Shiosai services are operated using Makuhari-based 9-car 255 series EMU and 5- or 10-car E257-500 series EMU formations. The E257-500 series formations have no Green (first class) cars.
Past rolling stock
Formations
Trains are formed as shown below, with car 1 at the Tokyo end.
9-car 255 series
Car 3 is reserved on some services, and car 5 is non-reserved on some services.
Past formations
Trains were originally formed of 9-car 183 series EMUs, including one Green car, or 6-car sets with no Green car, but from December 1994, services were formed of 8-car 183 series sets with the Green car removed, as shown below.
History
The Shiosai service was introduced from 10 March 1975 following the completion of electrification of the Sōbu Main Line in October 1974, using 9-car 183 series EMUs, replacing five of the seven daily diesel-powered Inubō (犬吠) express services that operated between Shinjuku/Ryōgoku and Chōshi.
From the start of the November 1982 timetable revision, further 183 series EMUs were drafted in, displaced from Toki limited express services following the opening of the Joetsu Shinkansen, and the remaining Inubō express services were discontinued and absorbed into the Shiosai services, giving seven return workings daily.
From the start of the revised timetable on 10 December 2005, 255 series 9-car EMUs were introduced on Shiosai services. From the same date, services were made entirely no-smoking.
From the start of the 14 March 2015 timetable revision, all Shiosai services started and terminated at Tokyo Station, with no services operating from Shinjuku.