London Underground Buses, Tramlink, London Overground, London River Services and Docklands Light Railway. Crossrail, due to open in 2019, is to be identified with a roundel. The 100th anniversary of the roundel was celebrated in 2008 by TfL commissioning 100 artists to produce works that celebrate the design. Seventy of the 270 London Underground stations use buildings that are on the Statutory List of Buildings of Special Architectural or Historic Interest, and five have entrances in listed buildings. The Metropolitan Railway's original seven stations were inspired by Italianate designs, with the platforms lit by daylight from above and by gas lights in
History of the London Underground early years of the 20th century, UD signs appeared outside stations in central London. World War I delayed extensions of the Bakerloo and Central London Railways, and people used the tube stations as shelters during air raids in 1915. After the war, government-backed financial guarantees were used to expand the network, and the tunnels of the City and South London and Charing Cross, Euston and Hampstead Railways were linked at Euston and Kennington, although the combined service was not named the Northern line until later. The Piccadilly line was extended north to Cockfosters and took over District line branches to