London's Underground system boasts the world's first urban underground line, the Metropolitan Railway. Its steam trains were first used by the public on 10 January 1863. This and all subsequent Victorian Underground lines were aimed at reaching the City of London, the central business district. By 1900, they had all been extended into the suburbs and a network of deep-level Tube lines was under construction. These lines had a huge influence on the growth of London throughout the late 19th and 20th centuries. There was no overall strategy for universal coverage, nor was there any state sponsorship. The early years were fraught with finding private finance for what was seen as a risky enterprise.
The early Underground lines were built using the 'cut and cover' method. A shallow cutting was dug along a road to take the tracks, and then roofed over to create a tunnel. Afterwards, the road was reinstated on top. These early lines of the Metropolitan and District, built in the 1860s and 70s, are all only just below ground level.
The Greathead shield, developed by James Henry Greathead, enabled deep-level Tubes to be safely built under London. The shield consists of an iron cylinder that protected miners while they dug a section of the tunnel and built the tunnel lining. The shield uses compressed air and hydraulic jacks to propel it forward. Similar technology is used today to build tunnels. These deep-level Tubes opened from 1890 onwards and were powered by electricity from the start.
Electrification of the older sections of the Underground was a great improvement. Steam polluted the air underground, even with surface vents and condensing apparatus, which fed the exhaust steam back into the engine's cold water tanks.
Between 1902 and 1914, the Underground Electric Railways of London (subsequently known as the Underground Group) took over all Underground lines apart from the Metropolitan and Waterloo and City lines. It proudly proclaimed that its lines used electric traction, powered by Lots Road Power Station in Chelsea. In 1933, the London Passenger Transport Board took charge of all London's transport networks except the overground services of the mainline companies. It was commonly known as London Transport (L.T), and ran Underground lines, bus and tram networks.
Metropolitan line The first section of the Metropolitan Railway opened in 1863 between Paddington and Farringdon. By 1876, this line had reached Mansion House. The westerly section from Paddington to South Kensington was completed in stages by 1868. A northwestern extension out of London through St John's Wood to Harrow and Aylesbury was completed by 1892. In 1904, the Harrow to Uxbridge line opened. In 1905, electric trains replaced steam on the Baker Street to Uxbridge section. In 1933, the Metropolitan Railway was taken over by the London Passenger Transport Board (L.P.T.B).
District line The District Railway was London's second Underground line, and originally used steam locomotion. In 1868, the line opened between Westminster Bridge and South Kensington, and soon extended to Blackfriars (1870). By 1884, services had reached New Cross, via the Thames Tunnel. From 1902 onwards the line was run by the U.E.R.L. In that year, services were also extended eastwards to Bromley and Barking. From 1905, electric trains replaced steam on the District line. From 1933, the line was run by the L.P.T.B.
Circle line The final link on the Circle line, then called the Inner Circle, was completed in 1884. It had the same shape as today: an irregular loop around Central London rather than a circle. It was made by joining up the two original Metropolitan and District lines at either end. It was jointly run by the two separate companies. The line was electrified in 1905 and became part of London Transport in 1933.
Hammersmith and City line This line was originally opened by the Great Western Railway between Westbourne Park and Hammersmith in 1864. In 1867, the undertaking was jointly vested in the Great Western Railway and the Metropolitan Railway. The line was electrified in 1906 and became part of the L.P.T.B. in 1933. It is essentially a branch of the Metropolitan line and shares the same tracks on the northern side of the Circle line.
East London line The East London Railway (E.L.R) opened to the public in 1869 through the Thames Tunnel, and was extended northwards to Shoreditch in 1876. When it was electrified in 1913, the Metropolitan Railway became the sole operator. From 1933, the L.P.T.B. owned 35% of the E.L.R and took over operation of its passenger services. After the formation of the British Transport Commission in 1948, L.T. took over ownership of the whole E.L.R.
Northern line This line was originally two lines, one called the City and South London Railway (C&S.L.R) and the other the Charing Cross, Euston, and Hampstead Railway (C.C.E & H.R). The C & S.L.R. was London's first deep Tube railway. It opened between King William Street in the City and Stockwell in December 1890. In 1900, it was extended to Moorgate Street in the north, and southwards to Clapham North. The C.C.E & H.R. line opened in 1907. The original extent was from the Strand (Charing Cross) in the south, splitting at Camden Town, where one fork went to Golders Green and the other to Highgate (now Archway). During the 1920s, the line was extended to Edgware (1924) and linked to C&S.L.R. to form the Northern line. In the late 1930s, the Highgate branch was extended to link up with an existing overground suburban railway at East Finchley, taking Tube trains on to High Barnet and Mill Hill East in 1939-40.
Waterloo and City line This line opened in 1898 to take commuters arriving at Waterloo to jobs in the City. It was London's second deep-level Tube railway and was run by The London and South Western Railway Company. It became part of British Railways Southern Region in 1948 when Britain's railways were nationalised. In 1994, it became part of London Underground, but there is no physical link with the rest of the system. It is a completely separate, short shuttle line.
Central line In 1900 the Central London Railway (C.L.R) as the line was originally known, opened between Shepherd's Bush and Bank. It was the first Tube line to connect the West End with the City. It was originally known as the 'Twopenny Tube' because of the flat fare. In 1912, the line was extended eastwards to Liverpool Street. By 1920, trains ran west to Ealing Broadway on Great Western Railway tracks. In the late 1940s, eastern extensions to the Central line opened: Liverpool Street to Stratford (1946) and Stratford to Leytonstone (1947). In 1947, the line was extended westwards between North Acton and Greenford. By 1948, the eastern loop through Epping and Hainault was completed. Most of this section involved linking up and electrifying existing suburban overground lines to become part of the Tube. In 1963, the Woodford to Hainault section was the first of London's Underground lines to use automatic train operation. The Central line is one of the lynchpins of the Underground network. An extensive programme of modernisation was undertaken in the 1990s to cope with rising passenger numbers.
Piccadilly line This line was originally called the Great Northern, Piccadilly, and Brompton Railway. It opened in December 1906 between Hammersmith and Finsbury Park. In 1932, extensions allowed passengers to travel north to Cockfosters and west to Hounslow and Uxbridge. The next major extension connected Heathrow Airport with central London in 1977. The loop to Terminal 4 was completed in 1986, and the line will serve the new Terminal 5.
Bakerloo line This was originally called the Baker Street and Waterloo Railway. It opened in 1906 between Baker Street and Elephant and Castle. It was the first Tube line owned by the Underground Group to open. The nickname Bakerloo, suggested by a journalist, was soon adopted as the line's official name. By 1915, the line was extended in stages to Queen's Park. Through trains ran over London and North Western Railway tracks from Queen's Park to Watford. These tracks were incorporated into the Bakerloo line in the 1930s. In 1939, Bakerloo line trains ran to Stanmore on what is now the northern section of the Jubilee line (since its opening in 1979).
Victoria line The initial section of the Victoria line opened in 1968 between Walthamstow Central and Warren Street. This was the first new Tube railway to cross central London in 60 years. In 1969, the line was extended to Victoria, providing a direct connection between the important mainline stations of Euston, King's Cross and Victoria. By 1971, the line was extended to Brixton. The Victoria line was designed to be more automated than the earlier stations, necessitating fewer staff. Automatic ticket issuing and checking was used. Trains were automatically driven and routed from a central control room by computer. The person in the cab does not actually drive the train but operates the doors, and is responsible for passenger safety.
Jubilee line The line was originally to be called the Fleet line, but its name changed during construction to celebrate the Queen's Silver Jubilee in 1977. It opened in 1979 between Stanmore and Charing Cross. The section between Baker Street and Stanmore was formerly part of the Bakerloo line, and only the part south of Baker Street was newly built. In 1999, an extension south of Bond Street to Westminster and Waterloo and east to Stratford opened, bypassing Charing Cross. The Jubilee line extension also served the new and redeveloped financial district in Docklands.