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
Line 1 (Ningbo Rail Transit) District. Then it passes Ningbo East New Town and then go overground. Finally the metro line extends into Beilun District and ends there. The section between Gaoqiao and Ningbo East New Town has been constructed as the first phase which started service on May 30, 2014. The rest section from Ningbo East New Town to Beilun District opens on March 19, 2016. The line has 28 stations in total, of which 12 are elevated and the rest are underground. Till June 2014, 20 stations of Line 1 are operational. Line 1 (Ningbo Rail Transit) Line 1 of Ningbo Rail Transit