Токио метросының Маруноучи желісі

Subway line in Tokyo, Japan

The Tokyo Metro Marunouchi Line (東京メトロ丸ノ内線) is a subway line in Tokyo, Japan, operated by Tokyo Metro. The line runs in a U shape between Ogikubo Station in Suginami and Ikebukuro Station in Toshima, with a branch line between Nakano Sakaue Station and Hōnanchō Station. The official name is Line 4 Marunouchi Line (4号線丸ノ内線). The line was named after the Marunouchi business district in Chiyoda, Tokyo, under which it passes. On maps, diagrams and signboards, the line is shown using the color red, and its stations are given numbers using the letters "M" for the main line and "Mb" for the branch line.

The Marunouchi Line is the second line to be built in the city, and the first one constructed after the Second World War. The route is U shaped, running from Ogikubo Station in the west of the city via the commercial and administrative district of Shinjuku through to the Marunouchi commercial center around Tokyo Station, before turning back and heading to Ikebukuro. Along with the Ginza Line, it is self enclosed and does not have any through services with other railway lines. The Marunouchi Line is served by Tokyo Metro 02 series rolling stock in six car trains on the main line, and mostly three car trains on the Hōnanchō branch (some six car trains during peak hours). The main line was the most frequent subway line in Tokyo, with trains once running at intervals of 1 minute 50 seconds during peak hours. In spite of such high frequency service, according to the 2018 survey by the Ministry of Land, Infrastructure, Transport and Tourism, the Marunouchi Line is one of the most crowded railway lines in Tokyo, running at 169% capacity between Shin ōtsuka and Myōgadani stations. Its age and relatively short train length has made it one of the most crowded lines in Tokyo, although the 2000 opening of the Toei Ōedo Line has relieved the problem somewhat. In response to crowding, Tokyo Metro upgraded all stations with chest high platform doors on March 28, 2009, a date on which it also began driver only operation. The Hōnanchō branch switched to driver only operation in July 2004. Due to the age of the Marunouchi Line and the relative shallowness at which it runs, at several points in central Tokyo trains run at or above ground level. These include Yotsuya Station, the Kanda River near Ochanomizu Station (see image), and between Kōrakuen and Myōgadani stations. On maps, diagrams and signboards, the line is shown using the color red. Its stations are given numbers using the prefix "M"; Hōnanchō branch line stations carry the prefix "Mb", which replaced the previously used lowercase "m" prefix in November 2016.

All stations are located in Tokyo. Some trains leave the main line at Nakano sakaue (M 06) for the Marunouchi Branch Line to Hōnanchō.

No. StationJapaneseDistance (km)TransfersLocationBetweenstationsFrom Ogikubo荻窪 –0.0Suginami南阿佐ケ谷1.51.5 新高円寺1.22.7 東高円寺0.93.6 新中野1.04.6 Nakano中野坂上1.15.7西新宿1.16.8 Shinjuku新宿0.87.6新宿三丁目0.37.9新宿御苑前0.78.6 四谷三丁目0.99.5 四ツ谷1.010.5赤坂見附1.311.8Minato国会議事堂前0.912.7Chiyoda霞ケ関0.713.4銀座1.014.4Chūō東京1.115.5Chiyoda大手町0.616.1淡路町0.917.0御茶ノ水0.817.8Bunkyō本郷三丁目0.818.6 Toei Oedo Line (E 08)後楽園0.819.4茗荷谷1.821.2 新大塚1.222.4 池袋1.824.2Toshima

No. StationJapaneseDistance (km)TransfersLocationBetweenstationsTotal方南町 –0.0 Suginami中野富士見町1.31.3 Nakano中野新橋0.61.9 中野坂上1.33.2

Marunouchi Line services are operated using a fleet of 53 Tokyo Metro 02 series six car EMUs in service since 1988 together with six three car sets used on Hōnanchō branch services until September 2022. All trains are based at Koishikawa and Nakano Depots. A fleet of 53 new Tokyo Metro 2000 series six car trains was scheduled to be introduced from fiscal 2018, replacing the 02 series trains by fiscal 2025. On February 23, 2019, the 2000 series started operation.

Communications based train control (CBTC) signalling is also scheduled to be introduced together with the new rolling stock from 2022.