Editing District line (section)

{{Short description|London Underground line}}
{{about|the London Underground line}}
{{Use dmy dates|date=February 2024}}
{{Use British English|date=January 2020}}
{{Infobox rail line
| name                            = District line
| logo                            = London flag boxes - Underground District line.svg
| logo_width                      = 250px
| logo_alt                        = 
| image                           = London Underground S7 Stock 21360 on District Line, Wimbledon (16081398792).jpg
| image_width                     = 250
| image_alt                       = 
| caption                         = A District line train at [[Wimbledon station|Wimbledon]] with a service to [[Edgware Road tube station (Circle, District and Hammersmith & City lines)|Edgware Road]], 2014
| type                            = [[Rapid transit]]
| system                          = [[London Underground]]
| start                           = Edgware Road, Upminster
| mapcolour                       = Green
| mapcolourlink                   = Tube map
| end                             = Richmond, Ealing Broadway, Wimbledon, Kensington (Olympia)
| stations                        = 60
| ridership2                      = 251.199 million (2019)<ref>{{cite web |title=London Assembly Questions to the Mayor |url=https://www.london.gov.uk/who-we-are/what-london-assembly-does/questions-mayor/find-an-answer/tube-usage-1|publisher=London Assembly |year=2022 |access-date=29 February 2024}}</ref> passenger journeys
| open                            = {{Start date and age|df=y|1868|12|24}}
| character                       = Sub-surface
| close                           = 
| depot                           = {{plainlist|
* [[Upminster Depot|Upminster]]
* [[Ealing Common Depot|Ealing Common]]
* [[Lillie Bridge Depot|Lillie Bridge]]
}}
| stock                           = [[S7 Stock]]
| linelength_km                   = 64
| tracklength_km                  = 
| gauge                           = {{Track gauge|sg|allk=on}}
| electrification                 = 750V DC and 630V DC on sections used by the Piccadilly line
| speed_mph                       = 62
| website                         = [http://www.tfl.gov.uk/ tfl.gov.uk]
| map_name                        = [[Transport for London]] {{nowrap|rail lines}}
| signalling                      = CBTC (East of Barons Court/Fulham Broadway)
Tripcock/Trainstop (West of Barons Court/Fulham Broadway)
| map                             = {{London rail lines}}
| map_state                       = collapsed
}}

The '''District line''' is a [[London Underground]] line running from {{stn|Upminster}} in the east and [[Edgware Road tube station (Circle, District and Hammersmith & City lines)|Edgware Road]] in the west to {{lus|Earl's Court}} in west London, where it splits into multiple branches. One branch runs to {{stn|Wimbledon}} in south-west London and a short branch, with a limited service, only runs for one stop to {{stn|Kensington (Olympia)}}.<ref>{{Cite web |url= http://content.tfl.gov.uk/wtt-150-district-20-may-2018.pdf |title=District line working timetable No. 150 |date=20 May 2018 |publisher= Transport for London |access-date=27 July 2019 |archive-date=27 July 2019 |archive-url= https://web.archive.org/web/20190727230717/http://content.tfl.gov.uk/wtt-150-district-20-may-2018.pdf |url-status=dead }}</ref> The main route continues west from Earl's Court to {{lus|Turnham Green}} after which it divides again into two western branches, to [[Richmond station (London)|Richmond]] and {{stn|Ealing Broadway}}.

Printed in green on the [[Tube map]], the line serves 60 stations (more than any other Underground line)<ref>[https://www.mylondon.news/news/zone-1-news/london-underground-lines-listed-longest-16745394 The London Underground lines listed from longest to shortest - MyLondon, 13 Aug 2019]</ref> over {{convert|64|km|mi|order=flip}}. It is the only Underground line to use a bridge to traverse the [[River Thames]], crossing on both the Wimbledon and Richmond branches.<ref>{{cite book |title= Underground Official Handbook |author=Bayman, Bob |year=2000 |publisher=Capital Transport |page=43}}</ref> The track and stations between {{stn|Barking}} and {{lus|Aldgate East}} are shared with the [[Hammersmith & City line]], and between {{lus|Tower Hill}} and {{lus|Gloucester Road}} and on the Edgware Road branch they are shared with the [[Circle line (London Underground)|Circle line]]. Some of the stations between {{lus|South Kensington}} and {{lus|Ealing Common}} are shared with the [[Piccadilly line]]. Unlike London's [[London Underground infrastructure#Subsurface versus deep-level tube lines|deep-level lines]], the railway tunnels are just below the surface, and the trains are of a similar size to those on British main lines.

The District line is the busiest of the sub-surface lines and the fifth-busiest line overall on the Underground, with over 250&nbsp;million passenger journeys recorded in 2019.<ref>{{cite web |title=Greater London Authority Questions to the Mayor |url=https://www.london.gov.uk/who-we-are/what-london-assembly-does/questions-mayor/find-an-answer/tube-usage-1|publisher=Greater London Authority |year=2022 |access-date=29 February 2024}}</ref> 

The original [[Metropolitan District Railway]] (as it was then called) opened in December 1868 from South Kensington to {{lus|Westminster}} as part of a plan for a below-ground "inner circle" connecting London's main line termini. At first, services were operated using wooden carriages hauled by steam locomotives. Electrification was financed by the American [[Charles Yerkes]], and electric services began in 1905. The railway was absorbed by the [[London Passenger Transport Board]] in 1933. In the first half of the 1930s, the Piccadilly line took over the Uxbridge and Hounslow branches, although a peak-hour District line service ran on the Hounslow branch until 1964. Kensington (Olympia) has been served by the District line since 1946, and a short branch to {{rws|South Acton|England}} closed in 1959. The trains carried [[Train guard|guards]] until [[one-person operation]] was introduced in 1985.

The signalling system is being upgraded (as part of the [[Four Lines Modernisation]] project) as of September 2019 and the previous [[D Stock]] trains were fully replaced by seven-car [[London Underground S7 and S8 Stock|S Stock]] trains in April 2017.