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
History of the London Underground Stratford, with through running from 22 November 1999, when the Charing Cross terminus closed. Transport for London (TfL) was created in 2000 as part of the Greater London Authority by the Greater London Authority Act 1999. In 1999, before control was passed to TfL, London Underground was split up so that a public–private partnership (PPP) arrangement could be put in place, with London Underground remaining a public company running the trains while private companies were responsible for upgrading the railway. Three packages of 30-year franchises were drawn up, covering the Jubilee, Northern and Piccadilly lines (JNP), the Bakerloo, Central Victoria