The
District line is a
London Underground service that crosses
Greater London from east to west. From
Upminster, the eastern terminus, the line runs through
Central London to
Earl's Court before dividing into three western branches, to
Ealing Broadway,
Wimbledon and
Richmond. There is a short branch that goes from Earl's Court to . A branch also runs north from Earl's Court to
Edgware Road via
Paddington. Coloured green on the
tube map, the line serves 60 stations in , and with bridges across the Thames on the Wimbledon and Richmond branches is the only London Underground line to cross the river in this way. The track and stations between
Barking and
Aldgate East are shared with the
Hammersmith & City line, and between
Tower Hill and
Gloucester Road and on the Edgware Road branch with the
Circle line. Some of the stations are shared with the
Piccadilly line. Of the 60 stations served, 25 are below ground. Unlike London's deep-level tube railways, the railway tunnels are just below the surface, and the trains are of a similar size to those on British main lines.