<P> The LPTB was nationalised in 1948, and the reconstruction of the mainline railways was given priority over the maintenance of the Underground . In 1953 an unpainted aluminium train entered service on the District line, and this became the standard for new trains . In the early 1960s the Metropolitan line was electrified as far as Amersham, and steam locomotives no longer hauled passenger trains . The Victoria line, a new tube line across central London, opened in 1968--71 with trains driven automatically . In 1976 the isolated Northern City Line was taken over by British Rail and linked up with the mainline railway at Finsbury Park . In 1979 another new route, the Jubilee line, took over part of the Bakerloo line; it was extended through the Docklands to Stratford in 1999 . </P> <P> Under the control of the Greater London Council, London Transport introduced in 1981 a system of fare zones for buses and underground trains that cut the average fare . Fares increased following a legal challenge but the fare zones were retained, and in the mid-1980s the Travelcard and the Capitalcard were introduced . In the early years of the 21st century, London Underground was reorganised in a public--private partnership where private companies upgraded and maintained the infrastructure . In 2003 control passed to Transport for London (TfL), which had been opposed to the arrangement and, following financial failure of the infrastructure companies, had taken full responsibility by 2010 . The contactless Oyster card first went on sale in 2003 . The East London line closed in 2007 to be converted into a London Overground line, and in December 2009 the Circle line changed from serving a closed loop around the centre of London to a spiral also serving Hammersmith . Currently there is an upgrade programme to increase capacity on several Underground lines, and work is under way on a Northern line extension to Battersea . </P> <P> In the first half of the 19th century, London had grown greatly and the development of a commuting population arriving by train each day led to traffic congestion with carts, cabs and omnibuses filling the roads . By 1850 there were seven railway termini located around the urban centre of London and the concept of an underground railway linking the City of London with these stations was first proposed in the 1830s . Charles Pearson, Solicitor to the City of London, was a leading promoter of several schemes, and he contributed to the creation of the City Terminus Company to build such a railway from Farringdon to King's Cross in 1852 . Although the plan was supported by the City of London, the railway companies were not interested and the company struggled to proceed . In 1854 the Metropolitan Railway (also known as the Met) was granted permission to build an underground line at an estimated cost of £ 1 million . With the Crimean War under way, the Met found it hard to raise the capital, and construction did not start until March 1860 . The railway was mostly built using the "cut - and - cover" method from Paddington to King's Cross; east of King's Cross it was built by tunnelling and then followed the culverted River Fleet in an open cutting to the new meat market at Smithfield . The 3.75 - mile (6 km) railway opened to the public on 10 January 1863, using steam locomotives hauling wooden carriages . It was hailed as a success, carrying 38,000 passengers on the opening day, borrowing trains from other railways to supplement the service . In the first twelve months 9.5 million passengers were carried and in the second twelve months this increased to 12 million . </P> <P> The Met's early success prompted a flurry of applications to parliament in 1863 for new railways in London, many competing for similar routes . The House of Lords established a select committee that recommended an "inner circuit of railway that should abut, if not actually join, nearly all of the principal railway termini in the Metropolis". Proposals to extend the Met were accepted, and the committee agreed a proposal that a new company, the Metropolitan District Railway (commonly known as the District Railway), be formed to complete the circuit . Initially, the District and the Met were closely associated and it was intended that they would merge . The Met's chairman and three other directors were on the board of the District, John Fowler was the engineer of both companies . The construction works for the extensions were let as a single contract and the Met initially operated all the services . Struggling under the burden of high construction costs, the District's level of debt meant that merger was no longer attractive to the Met and its directors resigned from the District's board . To improve its finances, the District terminated the operating agreement and began operating its own trains . Conflict between the Met and the District and the expense of construction delayed further progress on the completion of the inner circle . In 1879, the Met now wishing to access the South Eastern Railway via the East London Railway (ELR), an Act of Parliament was obtained to complete the circle and link to the ELR . After an official opening ceremony on 17 September and trial running, a complete Circle line service started on 6 October 1884 . </P>

Describe the original problem in london that led to the need for the underground
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