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Yokohama Municipal Subway line4 min read

Yokohama Municipal Subway Line 1 (Blue Line)

1号線

Trains and departures on this line are not shown on the map: the timetable data is withheld pending licensing.

Yokohama Municipal Subway Line 1 (1号線), branded as part of the Blue Line, is one of the two route designations that make up the longer of the two lines of the Yokohama Municipal Subway, owned and operated by the Yokohama City Transportation Bureau. Line 1 is the 19.7-kilometre southern portion, running from Kannai Station, the formal starting point, south and west through Kami-Ōoka and Totsuka to Shōnandai Station in Fujisawa, Kanagawa Prefecture.

It is operated as a single through service together with Line 3 (the 20.7 km Kannai–Azamino portion), and the two designations together total 40.4 km and carry the nickname "Blue Line," the second-longest subway line in Japan after Tokyo's Toei Ōedo Line. Built to 1,435 mm standard gauge and electrified at 750 V DC, the line is unusual among Japanese subways in drawing current from a third rail rather than overhead wire, and it is the most recent newly built subway line in Japan to do so.

YokohamaIsogo5 km
Route of the Yokohama Municipal Subway Line 1 (Blue Line) · Kanagawa · Boundaries: MLIT / GSI / Japan Post

History

The line grew out of the "Yokohama Six Major Projects" framework announced in October 1965, which positioned a subway as the backbone of the city's transport. On 15 July 1966 the Urban Transport Council's Report No. 9 recommended four subway lines (Lines 1–4) for the city to build, and Yokohama City Council approved the construction plan on 11 October 1966. Kannai was designated the junction of the Line 1 and Line 3 sections chosen for priority construction; the formal starting point of Line 1 is Kannai, although the operating origin of through services is Shōnandai. The line fitted automatic ticket gates at every station from its opening, a rarity in the Tokyo region at the time.

Passenger service began on 16 December 1972, when the 5.2 km first-phase section of Line 1 opened between Isezakichōjamachi and Kami-Ōoka with three-car 1000 series sets. The opening had slipped repeatedly: a July 1970 cloudburst flooded about 3 km of the partly built Kami-Ōoka–Yoshinochō section with some 500,000 tonnes of water and silt, taking about two months to clear, and a September 1972 typhoon then flooded the nearly finished platform at Isezakichōjamachi. Between them, the two floods moved the opening from a planned spring date to December.

On 4 September 1976 the second phase opened: Line 1 was extended 2.8 km southwest from Kami-Ōoka to Kaminagaya and north from Isezakichōjamachi to Kannai, and the first section of Line 3 opened from Kannai to Yokohama. From that day Line 1 and Line 3 began running through one another as a single service across Kannai, the operating pattern that still defines the line. With the completion of the Kaminagaya depot, trains were lengthened from three to five cars on 15 June 1977, and on 21 June 1984 the air-conditioned 2000 series entered service and six-car operation began.

The line then pushed south and west toward Totsuka. On 14 March 1985 the third phase extended Line 1 the 2.0 km from Kaminagaya to Maioka, opened as a single track, on the same day that Line 3 reached Shin-Yokohama. Line 1 reached Totsuka on 24 May 1987 as the fourth phase, though Totsuka opened only as a temporary station because work beneath the Japanese National Railways lines was running late; the permanent Totsuka station opened on 27 August 1989.

Line 1 was completed in 1999. On 29 August that year the sixth and final phase carried the line from Totsuka to Shōnandai, bringing Line 1 to its full 19.7 km and the through-operated Blue Line to its present 40.4 km; on the same day the intermediate "Shin-Yokohama-Kita" station on Line 3 was renamed Kita-Shin-Yokohama to avoid confusion with Shin-Yokohama. Station numbering, which now uses the prefix "B", was introduced in 2002, the line's thirtieth year, alongside a 2002 FIFA World Cup tie-in that decorated each of the 32 stations of the through line for one participating nation.

The Transportation Bureau settled on the combined name "Blue Line" for Lines 1 and 3 on 15 June 2006, and began using it formally on 30 March 2008, when the new Green Line opened and the two subway lines needed to be told apart. The 1000 and 2000 series both ended service on 16 December 2006; automatic train operation was switched on in January 2007, platform doors were fitted at every station, and driver-only (one-man) operation began on 15 December 2007. Every train had called at all stations until 18 July 2015, when limited-stop "Rapid" services started, cutting the Shōnandai–Azamino journey by up to ten minutes compared with local trains. The fleet is now formed of 3000 series and, from 2 May 2022, 4000 series sets, and the city is planning a further 6.5 km extension of Line 3 from Azamino to Shin-Yurigaoka.

Stations on this line

17 stations tracked on the map, listed alphabetically. Select any to read its page.

Timeline
  • 196615 July: Urban Transport Council Report No. 9 recommends four subway lines (Lines 1–4) for Yokohama to build; the city council approves the construction plan on 11 October.
  • 19681 October: the subway's groundbreaking ceremony is held.
  • 197216 December: the 5.2 km first-phase section of Line 1, Isezakichōjamachi–Kami-Ōoka, opens; three-car 1000 series sets begin revenue service.
  • 19764 September: second-phase opening — Line 1 extended 2.8 km from Kami-Ōoka to Kaminagaya and north from Isezakichōjamachi to Kannai, and the first Line 3 section (Kannai–Yokohama) opens; through operation between Line 1 and Line 3 begins at Kannai.
  • 197715 June: with the Kaminagaya depot completed, trains are lengthened from three to five cars.
  • 198421 June: the 2000 series, the line's air-conditioned trains, enters service; six-car operation begins the same day.
  • 198514 March: third-phase opening — Line 1 extended 2.0 km from Kaminagaya to Maioka (as a single track), the same day Line 3 reached Shin-Yokohama.
  • 198724 May: fourth-phase opening — Line 1 extended Maioka–Totsuka, with Totsuka opening as a temporary station because work beneath the JNR lines was delayed.
  • 198927 August: the permanent Totsuka station opens, replacing the 1987 temporary facility.
  • 199929 August: sixth and final phase — Line 1 extended Totsuka–Shōnandai, completing the 19.7 km Line 1 and bringing the through line to 40.4 km; 'Shin-Yokohama-Kita' on Line 3 is renamed Kita-Shin-Yokohama.
  • 2002Station numbering, which now uses the prefix 'B', is introduced; for the line's thirtieth year, each of the through line's 32 stations is decorated for one nation in a 2002 FIFA World Cup tie-in.
  • 200615 June: the Transportation Bureau decides on the combined name 'Blue Line' for Lines 1 and 3; the 1000 and 2000 series both end service on 16 December.
  • 200715 December: driver-only (one-man) operation begins, after automatic train operation was switched on (20 January) and platform doors were installed across the line.
  • 200830 March: the name 'Blue Line' comes into formal use as the Green Line opens and the two subway lines need to be distinguished.
  • 201518 July: limited-stop 'Rapid' services begin, cutting the Shōnandai–Azamino journey by up to ten minutes compared with local trains.
  • 20222 May: the 4000 series enters service, built to replace the first-batch 3000A sets.

Sources

Last updated 16 October 2026.

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