Metropolitan line the top green light over a yellow light, and clear two green lights. The Metropolitan line's suburban rail character opposed to other London Underground lines is also shown by the long distances between stops. Eight of the top 10 furthest apart stations on the Underground are on the Metropolitan line. The section between Chalfont & Latimer and Chesham is the longest at , whilst the Finchley Road to Wembley Park section is the second longest, and Rickmansworth to Chorleywood the fourth longest overall. The Metropolitan line is the only London Underground line to operate an express service. Designed for commuters
London Underground L Stock London Underground L Stock London Underground L Stock was a clerestory-roofed rail stock built for the District line in 1932 and subsequently absorbed into the London Underground Q Stock, being redesignated Q31 Stock. The L Stock trains were built to provide additional rolling stock for the eastward extension of the District Line from Barking to Upminster. Two new electrified tracks were added parallel to the existing steam-operated LMS lines, including several new stations such as Upminster Bridge. Forty-five cars were built by the Union Construction Company, eight were driving motor cars and the rest were trailers. The eight motor cars,