London Underground with smaller trains that run in two circular tunnels ("tubes") with a diameter about . These lines have the exclusive use of a pair of tracks, except for the Piccadilly line, which shares track with the District line between Acton Town and Hanger Lane Junction and with the Metropolitan line between Rayners Lane and Uxbridge; and the Bakerloo line, which shares track with London Overground services north of Queen's Park. Fifty-five per cent of the system runs on the surface. There are of cut-and-cover tunnel and of tube tunnel. Many of the central London underground stations on deep-level tube routes
Guadalajara light rail system the large numbers of users of the rail system, there are plans to extend Line 2 to the west and to build a third line. Line 1 runs underground in the city center, but runs "at grade" north and south of the city center, and its surface sections include several level crossings, protected by crossing gates. The station platforms accommodate trains composed of no more than two cars. Line 2 is entirely underground except for a non-passenger section at its east end, connecting the last station to the maintenance facility. Its stations are long enough to accommodate trains of up