The London Underground all of which is now commonly referred to as the Tube, though originally this designation referred only to the deep-level lines, as distinct from the sub-surface lines is the oldest, and second longest metro system in the world, dating from 1863. The system serves 270 stations and was formed from several private companies, including the world's first underground electric line, the City and South London Railway.
Over three million journeys a day are made on the Underground network, over 1 billion journeys each year. An investment programme is attempting to address congestion and reliability problems, including £7 billion (?10 billion) of improvements planned for the Olympics.] London has been commended as the city with the best public transport. The Docklands Light Railway, which opened in 1987, is a second, more local metro system using smaller and lighter tram-type vehicles serving Docklands and Greenwich.
There is an extensive above-ground suburban railway network, particularly in South London, which has fewer Underground lines. London houses Britain's busiest station Waterloo with over 184 millon people using the interchange station complex each year. The stations have services to South East & South West London, and also parts of South East and South West England. Most rail lines terminate around the centre of London, running into fourteen terminal stations with the exception of the Thameslink trains connecting Bedford in the north and Brighton in the south via Luton and Gatwick Airports.
Since 2007 High-speed Eurostar trains link St Pancras International with Lille, Paris, and Brussels. Journey times to Paris and Brussels of 2h 15 and 1h 51 respectively make London closer to continental Europe than the rest of Britain by virtue of the High Speed 1 rail link to the Channel Tunnel while the first high speed domestic trains started in June 2009 linking Kent to London.