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
Economy of the London Borough of Croydon Economy of the London Borough of Croydon Croydon, located in Greater London, England, has a diverse economy with the service and retail sectors now dominating over the town's historical market status. It is today served well by its extensive rail network centering on East and West Croydon stations, from where London Overground, First Capital Connect and Southern operate to most parts of Greater London, Surrey, Sussex, Hampshire and the East of England. With the A23, M23 and M25 orbital motorway intersecting Croydon to the South East, it is the principal gateway of the motorway network from the East Sussex area