History of the London Underground to determine the cause. Following the incident, a system that stops a train automatically if the driver fails to brake was introduced at dead-ends on the London Underground. The Northern City Line was connected to British Rail tracks at Finsbury Park in the 1970s. The last tube train ran in October 1975, and British Rail services began in 1976. In 1977, the Piccadilly line was extended from Hounslow to Heathrow Airport, and in 1986 a platform serving Terminal 4 opened on a loop line. The Fleet line through central London was first proposed in 1965, taking over the Bakerloo line's
London Underground ticketing as 'auto top-up'. Tickets and pay as you go credit can be purchased via a website or over the telephone. The Oyster card system is designed to eliminate the need to purchase tickets at the station for most users. Following the implementation of the technology London Underground reduced the number of staff working in ticket offices. Contactless Visa, Maestro, MasterCard and American Express debit and credit bank cards issued in the UK, as well as contactless enabled smartphones and smartwatches using Apple Pay and Android Pay are accepted for travel on London Underground, London Overground, Docklands Light Rail, most National