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
Public transport in the London Borough of Havering Public transport in the London Borough of Havering Public transport in the London Borough of Havering, in northeast London, England, is a mix of National Rail, London Underground, London Overground and Crossrail and London Buses services. Rail services are primarily radial to central London with bus services providing most of the orbital connections. The public transport authority is Transport for London and the local authority is Havering London Borough Council. Several railway lines cross the borough running radial to central London. The Great Eastern Main Line has stations at Romford, Gidea Park and Harold Wood, with TfL Rail and Abellio