Airports of London cannot be expanded due to the docks on either side. It is also the only airport serving London which does not operate at night. A light rail service from London City Airport DLR station, which adjoins the terminal building of London City Airport, links it to the financial district of the City of London at Bank and Monument stations, which offer interchanges with London Underground. Located in the London Borough of Hillingdon, Heathrow is by far the largest of London's airports and considered the main gateway into the United Kingdom for non-European visitors. Heathrow has four terminals and two parallel
Automation of the London Underground Automation of the London Underground Automation of London Underground rolling stock has been partially implemented since the introduction of automatic train operation on the Hainault to Woodford section of the Central line in 1964. It is currently in use on four lines. Transport for London plans to extend this to other lines by 2022. Partially automated trains using Automatic Train Operation (ATO) have been used on passenger services on the Victoria line since 1968. The side doors to the driver's cab were sealed, so that access was normally through the passenger saloon. Since the trains were to be operated by