London Underground
A Central line train at Lancaster Gate
Background
Locale	Greater London, Chiltern, Epping Forest, Three Rivers and Watford
Transit type	Rapid transit
Number of lines	11
Number of stations	270 served (260 owned)
Daily ridership	3.04 million (approximate)[1] 3.4 million (weekdays) (approximate)[2]
Website	www.tfl.gov.uk/tube
Operation
Began operation	10 January 1863
Operator(s)	Transport for London (TfL)
Technical
System length	402 kilometres (250 mi)
Track gauge	1,435 mm (4 ft 8 1⁄2 in) Standard gauge
Electrification	630 V DC Fourth rail
System map

Part of a series of articles on The Tube
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The London Underground (often shortened to the Underground) is a rapid transit system in the United Kingdom, serving a large part of Greater London and some parts of Buckinghamshire, Hertfordshire and Essex. It incorporates the oldest section of underground railway in the world, which opened in 1863 and now forms part of the Circle, Hammersmith & City, and Metropolitan lines;^[3] and the first line to operate electric trains, in 1890, now part of the Northern line.^[4]

The Underground system is also colloquially called the Tube. As commonly used today both by Londoners and in most official publicity, this term embraces the entire system.^[5] Originally, though, it applied only to the deep-level lines with trains of a smaller and more circular cross-section, and served to distinguish them from the sub-surface "cut-and-cover" lines that were built first and originally used steam locomotives.

The earlier lines of the present London Underground network were built by various private companies. They became part of an integrated transport system in 1933 when the London Passenger Transport Board (LPTB) or London Transport was created. The underground network became a separate entity in 1985, when the UK Government created London Underground Limited (LUL).^[6] Since 2003 LUL has been a wholly owned subsidiary of Transport for London (TfL), the statutory corporation responsible for most aspects of the transport system in Greater London, which is run by a board and a commissioner appointed by the Mayor of London.^[7]

The Underground serves 270 stations and has 402 kilometres (250 mi) of track, 45 per cent of which is underground.^[8] It is the second largest metro system in the world in terms of route miles, after the Shanghai Metro^[9] and part of the largest system in terms of route miles when taken together with the Docklands Light Railway and the London Overground.^{[citation needed][10]} It also has one of the largest numbers of stations. In 2007, more than one billion passenger journeys were recorded,^[2] making it the third busiest metro system in Europe, after Moscow and Paris. The tube is an international icon for London, with the tube map, considered a design classic, having influenced many other transport maps worldwide. Although also shown on the Tube map, the Docklands Light Railway (DLR) and London Overground are not part of the London Underground network.

Currently, 86% of operational expenditure on the London Underground is covered by passenger fares.^[11] Almost all London Underground trains currently lack air-conditioning, which leads to the network getting very hot in the summer, although plans are under way to mitigate this problem with new air-conditioned trains and other schemes.^[12] Because of engineering work being carried out under the 2010–2012 upgrade plan, lines were regularly closed during weekends.^[13]

History[link]

Railway construction in the United Kingdom began in the early 19th century, and six railway terminals had been built just outside the centre of London by 1854: London Bridge, Euston, Paddington, King's Cross, Bishopsgate and Waterloo.^[14] At this point, only Fenchurch Street station was located in the actual City of London. Traffic congestion in the city and the surrounding areas had increased significantly in this period, partly due to the need for rail travellers to complete their journeys into the city centre by road. The idea of building an underground railway to link the City of London with the mainline terminals had first been proposed in the 1830s, but it was not until the 1850s that the idea was taken seriously as a solution to traffic congestion.^[14]

The first underground railways[link]

In 1855 an Act of Parliament was passed approving the construction of an underground railway between Paddington Station and Farringdon Street via King's Cross which was to be called the Metropolitan Railway. The Great Western Railway (GWR) gave financial backing to the project when it was agreed that a junction would be built linking the underground railway with its mainline terminus at Paddington. The GWR also agreed to design special trains for the new subterranean railway.

Construction of the Metropolitan Railway near King's Cross station, 1861

A shortage of funds delayed construction for several years. The fact that this project got under way at all was largely due to the lobbying of Charles Pearson, who was Solicitor to the City of London Corporation at the time. Pearson had supported the idea of an underground railway in London for several years. He advocated plans for the demolition of the unhygienic slums which would be replaced by new accommodation for their inhabitants in the suburbs, with the new railway providing transportation to their places of work in the city centre. Although he was never directly involved in the running of the Metropolitan Railway, he is widely credited with being one of the earliest visionaries behind the concept of underground railways. And in 1859 it was Pearson who persuaded the City of London Corporation to help fund the scheme. Work finally began in February 1860, under the guidance of chief engineer John Fowler. Pearson died before the work was completed.

The Metropolitan Railway opened on 10 January 1863,^[6] and was carrying over 26,000 passengers a day within a few months of opening.^[15] The Hammersmith and City Railway was opened on 13 June 1864 between Hammersmith and Paddington. Services were initially operated by GWR between Hammersmith and Farringdon Street. By April 1865 the Metropolitan had taken over the service. On 23 December 1865 the Metropolitan's eastern extension to Moorgate Street opened. Later in the decade other branches were opened to Swiss Cottage, South Kensington and Addison Road, Kensington (now known as Kensington Olympia). The railway was initially dual gauge, allowing for the use of the GWR's broad-gauge rolling stock as well as the more widely used standard-gauge stock. Disagreements with GWR forced the Metropolitan to switch to standard gauge in 1863 after the GWR withdrew all its stock from the railway. These differences were later patched up. Broad-gauge trains ceased to run on the Metropolitan in March 1869.

On 24 December 1868, the Metropolitan District Railway began operating between South Kensington and Westminster using Metropolitan Railway trains and carriages. The company, which soon became known as "the District", was first incorporated in 1864 to complete an Inner Circle railway around London in conjunction with the Metropolitan. This was part of a plan to build both an Inner Circle line and Outer Circle line.

A fierce rivalry soon developed between the District and the Metropolitan. This severely delayed the completion of the Inner Circle project as the two companies competed to build far more financially lucrative railways in the suburbs of London. The London and North Western Railway (LNWR) began running its Outer Circle service from Broad Street via Willesden Junction, Addison Road and Earl's Court to Mansion House in 1872. The Inner Circle was not completed until 1884, with the Metropolitan and the District jointly running services. In the meantime, the District had finished its route between West Brompton and Blackfriars in 1870, with an interchange with the Metropolitan at South Kensington. In 1877, it began running its own services from Hammersmith to Richmond, on a line originally opened by the London & South Western Railway (LSWR) in 1869. The District then opened a new line from Turnham Green to Ealing in 1879^[16] and extended its West Brompton branch to Fulham in 1880. Over the same decade the Metropolitan was extended to Harrow-on-the-Hill station in the north-west.

The early tunnels were dug mainly using cut-and-cover construction methods. This caused widespread disruption, and required the demolition of many properties on the surface. The first trains were steam-hauled, requiring effective ventilation to the surface. Ventilation shafts at various points on the route allowed the engines to expel steam and bring fresh air into the tunnels. One such vent is at Leinster Gardens, W2.^[17] To preserve the visual characteristics in what is still a well-to-do street, a five-foot-thick (1.5 m) concrete façade was constructed to resemble a genuine house frontage.

On 7 December 1869 the London, Brighton and South Coast Railway (LB&SCR) started operating between Wapping and New Cross Gate on the East London Railway (ELR) using the Thames Tunnel built by Marc Brunel and his son Isambard Kingdom Brunel, using the revolutionary tunnelling shield method which made its construction possible. This had opened in 1843 as a pedestrian tunnel, but in 1865 it was bought by the ELR (a consortium of six railway companies: the Great Eastern Railway (GER); London, Brighton and South Coast Railway (LB&SCR); London, Chatham and Dover Railway (LCDR); South Eastern Railway (SER); Metropolitan Railway; and the Metropolitan District Railway) and converted into a railway tunnel. In 1884 the District and the Metropolitan began to operate services on the line.

By the end of the 1880s, underground railways reached Chesham on the Metropolitan, Hounslow, Wimbledon and Whitechapel on the District and New Cross on the East London Railway. By the end of the 19th century, the Metropolitan had extended its lines far outside London to Aylesbury, Verney Junction and Brill, creating new suburbs along the route, later publicised by the company as Metro-land. Right up until the 1930s the company maintained ambitions to be considered as a main line rather than an urban railway, ambitions that are still continued somewhat today.

First tube lines[link]

The nickname "the Tube" comes from the circular tube-like tunnels through which the trains travel. Northern Line train leaving a tunnel mouth just north of Hendon Central station.

Following advances in the use of tunnelling shields, electric traction and deep-level tunnel designs, later railways were built deeper underground. This caused much less disruption at ground level, and it was therefore cheaper than and preferable to the cut-and-cover construction method.

The City & South London Railway (C&SLR, now part of the Northern Line) opened in 1890, between Stockwell and the now closed original terminus at King William Street. It was the first "deep-level" electrically operated railway in the world.^[18] By 1900 it had been extended at both ends, to Clapham Common in the south and Moorgate Street (via a diversion) in the north. The second such railway, the Waterloo and City Railway (W&CR), opened in 1898.^[19] It was built and run by the London and South Western Railway.

On 30 July 1900, the Central London Railway (now known as the Central Line) was opened,^[19] operating services from Bank to Shepherd's Bush. It was nicknamed the "Twopenny Tube" for its flat fare and cylindrical tunnels;^[20] the "tube" nickname was eventually transferred to the Underground system as a whole. An interchange with the C&SLR and the W&CR was provided at Bank. Construction had also begun in August 1898 on the Baker Street & Waterloo Railway, but work came to a halt after 18 months when funds ran out.^[21]

Integration[link]

The Circle Line and District Line platforms at Embankment station built using the original cut and cover method.

Tube map from 1908

Tube map from 1926

In the early 20th century the presence of six independent operators running different Underground lines caused passengers substantial inconvenience; in many places passengers had to walk some distance above ground to change between lines. The costs associated with running such a system were also heavy, and as a result many companies looked to financiers who could supply the capital they needed to expand into the lucrative suburbs as well as electrify the earlier steam-operated lines. The most prominent of these was Charles Yerkes, an American tycoon who secured the right to build the Charing Cross, Euston and Hampstead Railway (CCE&HR) on 1 October 1900, today also part of the Northern Line. In March 1901, he effectively took control of the District and this enabled him to form the Metropolitan District Electric Traction Company (MDET) on 15 July 1901. Through this he acquired the Great Northern and Strand Railway and the Brompton and Piccadilly Circus Railway in September 1901, the construction of which had already been authorised by Parliament, together with the moribund Baker Street & Waterloo Railway in March 1902. The GN&SR and the B&PCR evolved into the present-day Piccadilly Line. On 9 April the MDET became the Underground Electric Railways Company of London (UERL). The UERL also owned three tramway companies and went on to buy the London General Omnibus Company, creating an organisation colloquially known as "the Combine" which went on to dominate underground railway construction in London until the 1930s.

With the financial backing of Yerkes, the District opened its South Harrow branch in 1903 and completed its link to the Metropolitan's Uxbridge branch at Rayners Lane in 1904, although services to Uxbridge on the District did not begin until 1910 due to yet another disagreement with the Metropolitan. Today, District Line services to Uxbridge have been replaced by the Piccadilly Line. By the end of 1905, all District Railway and Inner Circle services were run by electric trains.

The Baker Street & Waterloo Railway opened in 1906, soon branding itself the Bakerloo and, by 1907, it had been extended to Edgware Road in the north and Elephant & Castle in the south. The newly named Great Northern, Piccadilly and Brompton Railway, combining the two projects acquired by MDET in September 1901, also opened in 1906. With tunnels at an impressive depth of 200 feet (61 m) below the surface, it ran from Finsbury Park to Hammersmith; a single station branch to Strand (later renamed Aldwych) was added in 1907. In the same year the CCE&HR opened from Charing Cross to Camden Town, with two northward branches, one to Golders Green and one to Highgate (now Archway).

Independently of the "Combine", the Great Northern & City Railway opened in 1904 between Finsbury Park and Moorgate. It was the only tube line of sufficient diameter to be capable of handling main line stock, and it was originally intended to be part of a main line railway. However, money soon ran out and the route remained separate from the main line network until the 1970s. The C&SLR was also extended northwards to Euston by 1907.

In early 1908, in an effort to increase passenger numbers, the underground railway operators agreed to promote their services jointly as "the Underground", publishing joint advertisements and creating a free publicity map of the network for the purpose. The map featured a key labelling the Bakerloo Railway, the Central London Railway, the City & South London Railway, the District Railway, the Great Northern & City Railway, the Hampstead Railway (the shortened name of the CCE&HR), the Metropolitan Railway and the Piccadilly Railway. Other railways appeared on the map but with much less prominence; these included the Waterloo & City Railway and part of the ELR, which were both owned by main-line railway companies at the time. As part of the process, "The Underground" name appeared on stations for the first time^[8] and electric ticket-issuing machines were also introduced. This was accompanied by the first appearance of the famous circle and horizontal bar symbol, known as "the roundel".^[22] In January 1933 the UERL experimented with a new diagrammatic map of the Underground, designed by Harry Beck and first issued in pocket-sized form. It was an immediate success with the public and is now commonly regarded as a design classic; an updated version is still in use today.^[23]

Meanwhile, on 1 January 1913 the UERL absorbed two other independent tube lines, the C&SLR and the Central London Railway. As the Combine expanded, only the Metropolitan stayed away from this process of integration, retaining its ambition to be considered as a main-line railway. Proposals were put forward for a merger between the two companies in 1913 but the plan was rejected by the Metropolitan. In the same year the company asserted its independence by buying out the cash-strapped Great Northern and City Railway, a predecessor to the Piccadilly Line. It also sought a character of its own. The Metropolitan Surplus Lands Committee had been formed in 1887 to develop accommodation alongside the railway, and in 1919 Metropolitan Railway Country Estates Ltd was founded to capitalise on the post-World War One demand for housing. This ensured that the Metropolitan would retain an independent image until the creation of London Transport in 1933.

The Metropolitan also sought to electrify its lines. The District and the Metropolitan had agreed to use the low-voltage DC system for the Inner Circle, comprising two electric rails to power the trains, back in 1901. At the start of 1905, electric trains began to work the Uxbridge branch, and from 1 November 1906 electric locomotives took trains as far as Wembley Park, where steam locos took over. This changeover point was moved to Harrow-on-the-Hill on 19 July 1908. The Hammersmith & City branch had also been upgraded to electric working on 5 November 1906. The electrification of the ELR followed on 31 March 1913, the same year as the opening of its extension to Whitechapel and Shoreditch. Following the Grouping Act of 1921, which merged all the cash-strapped main-line railways into four companies (thus obliterating the original consortium that had built the ELR), the Metropolitan agreed to run passenger services on the line.

The Bakerloo Line extension to Queen's Park was completed in 1915, and the service extended to Watford Junction via the London and North Western Railway tracks in 1917. The extension of the Central Line's branch to Ealing Broadway was delayed by the war until 1920.

The major development of the 1920s was the integration of the CCE&HR and the C&SLR and extensions to form what was to become the Northern line. This necessitated enlargement of the older parts of the C&SLR, which had been built on a modest scale. The integration required temporary closures during 1922—24. The Golders Green branch was extended to Edgware in 1924, and the southern end was extended from Clapham Common to Morden in 1926 with new stations designed by Charles Holden.^[24] Through Holden's work as consulting architect, designing new stations during the 1920s and 1930s, London Underground was modernised and every aspect of design carefully integrated.^[25]

The Watford branch of the Metropolitan opened in 1925, and in the same year electrification was extended to Rickmansworth. The last major work completed by the Metropolitan was the branch to Stanmore, which opened in 1932 and is now part of the Jubilee Line.

By 1933 the Combine had completed the Cockfosters extension of the Piccadilly Line, with through services running (via realigned tracks between Hammersmith and Acton Town) to Hounslow West and Uxbridge. The extension of the Piccadilly line was heavily promoted by London Underground.^[26]

London Transport[link]

In 1933 the Combine, the Metropolitan and all the municipal and independent bus and tram undertakings in London were required by central government to merge into a new London Passenger Transport Board (LPTB), a self-supporting and unsubsidised public corporation which came into being on 1 July 1933. The LPTB soon became known for short as London Transport (LT).

Shortly after it was created, LT began the process of integrating the underground railways of London into a single network. All the separate railways were renamed as "lines" within the system: the first LT version of Beck's map featured the District Line, the Bakerloo Line, the Piccadilly Line, the Edgware, Highgate and Morden Line, the Metropolitan Line, the Metropolitan Line (Great Northern & City Section), the East London Line, and the Central London Line. The shorter names Central Line and Northern Line were adopted for two lines in 1937. The Waterloo & City line was not originally included, as it was still owned by a main-line railway and not part of LT, but was added to the map in a less prominent style, also in 1937. LT announced a scheme for the expansion and modernisation of the network entitled the New Works Programme, which had followed the announcement of improvement proposals for the Metropolitan Line. This consisted of plans to extend some lines, to take over the operation of others from main-line railway companies, and to electrify the entire network. During the 1930s and 1940s, several sections of main-line railway were converted into surface lines of the Underground system. The oldest part of today's Underground network is the Central line between Leyton and Loughton, which had opened as a railway seven years before the Underground itself.

Londoners sheltering from the Blitz in a tube station

LT also sought to abandon routes which made a significant financial loss. Soon after the LPTB started operating, services to Verney Junction and Brill on the Metropolitan Railway were ended. The renamed Metropolitan Line's northern terminus thus became Aylesbury.

The outbreak of World War II delayed all the expansion schemes. From mid-1940, the Blitz led to the use of many Underground stations as shelters during air raids and overnight. The Underground helped over 200,000 children escape to the countryside and sheltered another 177,500 people. The authorities initially tried to discourage and prevent people from sleeping in the tube, but later supplied 22,000 bunks, latrines, and catering facilities. After a time there were even special stations with libraries and classrooms for night classes. Later in the war, eight London deep-level shelters were constructed under stations, ostensibly to be used as shelters (each deep-level shelter could hold 8,000 people) though plans were in place to convert them for a new express line parallel to the Northern line after the war. Some stations (now mostly disused) were converted into government offices: for example, Down Street was used for the headquarters of the Railway Executive Committee and was also used for meetings of the War Cabinet before the Cabinet War Rooms were completed;^[27] Brompton Road was used as a control room for anti-aircraft guns and the remains of the surface building are still used by London's University Royal Naval Unit (URNU) and University London Air Squadron (ULAS).

After the war, one of the last acts of the LPTB was to give the go-ahead for the completion of the postponed Central Line extensions. The western extension to West Ruislip was completed in 1948, and the eastern extension to Epping in 1949; the single-line branch from Epping to Ongar was taken over and electrified in 1957.

Nationalisation[link]

A D78 Stock train at Mansion House tube station on the District line, one of the busiest lines on the tube system.

On 1 January 1948, London Transport was nationalised by the Labour government, together with the four remaining main-line railway companies, and incorporated into the operations of the British Transport Commission (BTC). The LPTB was replaced by the London Transport Executive (LTE). This brought the Underground under the direct remit of central government for the first time in its history. The BTC prioritised the reconstruction of its main-line railways over the maintenance of the Underground network. The unfinished parts of the New Works Programme were gradually shelved or postponed.

However, the BTC did authorise the completion of the electrification of the network, seeking to replace steam locomotives on the parts of the system where they still operated. This phase of the programme was completed when the Metropolitan line was electrified to Chesham in 1960. Steam locomotives were fully withdrawn from London Underground passenger services on 9 September 1961, when British Railways took over the operations of the Metropolitan line between Amersham and Aylesbury. The last steam shunting and freight locomotive was withdrawn from service in 1971.^[28]

In 1963, the LTE was replaced by the London Transport Board, directly accountable to the Ministry of Transport.

GLC control[link]

Two 1973 Stock trains at Hammersmith tube station on the Piccadilly line.

On 1 January 1970, the Greater London Council (GLC) took over responsibility for London Transport, again under the formal title London Transport Executive. This period is perhaps the most controversial in London's transport history, characterised by staff shortages and a severe lack of funding from central government. In 1980 the Labour-led GLC began the 'Fares Fair' project, which increased local taxation to reduce ticket prices. The campaign was initially successful, and use of the Tube significantly increased. But serious objections to the policy came from the London Borough of Bromley, an area of London which has no Underground stations. The Council resented the subsidy, as it would be of little benefit to its residents. The council took the GLC to the Law Lords, who ruled that the policy was illegal based on their interpretation of the Transport (London) Act 1969. They ruled that the Act stipulated that London Transport must plan, as far as was possible, to break even. In line with this judgement, 'Fares Fair' was therefore reversed, leading to a 100% increase in fares in 1982 and a subsequent decline in passenger numbers. The scandal prompted Margaret Thatcher's Conservative Government to remove London Transport from the GLC's control in 1984, a development that turned out to be a prelude to the abolition of the GLC in 1986.

This period saw the first real postwar investment in the network with the opening of the Victoria line, built on a diagonal northeast-southwest alignment beneath central London and incorporating centralised signalling control with automatically driven trains. It opened in stages between 1968 and 1971. The Piccadilly line was extended to Heathrow Airport in 1977, and the Jubilee Line was opened in 1979, taking over the Stanmore branch of the Bakerloo line, with new tunnels between Baker Street and Charing Cross. There was also one important legacy from the 'Fares Fair' scheme: the introduction of ticket zones, which remain in use today.

London Regional Transport[link]

Street entrance to Oxford Circus tube station, one of the busiest on the network.

Jubilee line platforms at Westminster tube station opened in 1999 as part of the Jubilee line extension.

In 1984 the Conservative Government removed London Transport from the GLC's control, replacing it with London Regional Transport (LRT) on 19 June 1984 – a statutory corporation for which the Secretary of State for Transport was directly responsible. The government planned to modernise the system while slashing its subsidy from taxpayers and ratepayers. As part of this strategy, London Underground Limited was set up on 1 April 1985 as a wholly owned subsidiary of LRT to run the network.

The prognosis for LRT was good. Oliver Green, the then Curator of the London Transport Museum, wrote in 1987:

In its first annual report, London Underground Ltd was able to announce that more passengers had used the system than ever before. In 1985–86 the Underground carried 762 million passengers – well above its previous record total of 720 million in 1948. At the same time costs have been significantly reduced with a new system of train overhaul and the introduction of more driver-only operation. Work is well in hand on the conversion of station booking offices to take the new Underground Ticketing System (UTS)...and prototype trials for the next generation of tube trains (1990) stock started in late 1986. As the London Underground celebrates its 125th anniversary in 1988, the future looks promising.^[29]

However, cost-cutting did not come without critics. At 19:30 on 18 November 1987, a massive fire swept through the King's Cross St Pancras tube station, the busiest station on the network, killing 31 people. The fire had started in an escalator shaft to the Piccadilly Line, which was burnt out along with the top level (entrances and ticket hall) of the deep-level tube station. The escalator on which the fire started had been built just before World War II. The steps and sides of the escalator were partly made of wood, meaning that they burned quickly and easily. Although smoking was already banned on the subsurface sections of the London Underground in February 1985 as a consequence of the 1984 Oxford Circus fire, the Kings Cross fire was most probably caused by a commuter discarding a burning match, which fell down the side of the escalator onto the running track (Fennell 1988, p. 111). The running track had not been cleaned for some time and was covered in grease and fibrous detritus. The Member of Parliament for the area, Frank Dobson, informed the House of Commons that the number of transportation employees at the station, which handled 200,000 passengers every day at the time, had been cut from 16 to ten, and the cleaning staff from 14 to two.^[30] The event led to the abolition of all wooden escalators at all Underground stations and pledges of greater investment.

In 1994, with the privatisation of British Rail, LRT took control of the Waterloo and City Line, incorporating it into the Underground network for the first time. That year also saw the end of services on the little-used Epping-Ongar branch of the Central Line and the Aldwych branch of the Piccadilly Line after it was agreed that necessary maintenance and upgrade work would not be cost-effective.

In 1999 the Jubilee Line Extension to Stratford in London's East End was completed. This plan included the opening of a completely refurbished interchange station at Westminster. The Jubilee line's old terminal platforms at Charing Cross were closed but maintained operable for emergencies and film shoots.

Public–private partnership[link]

Underground entrance at Waterloo station, the busiest rail station in the UK.

Transport for London (TfL) replaced LRT in 2000, a development that coincided with the creation of a directly elected Mayor of London and the London Assembly. In January 2003 the Underground began operating as a Public-Private Partnership (PPP), whereby the infrastructure and rolling stock were maintained by two private companies (Metronet and Tube Lines) under 30-year contracts, while London Underground Limited remained publicly owned and operated by TfL.

The National Audit Office in a 2004 report on the PPP stated that the Department of Transport, London Regional Transport and London Underground Limited spent £180m in structuring, negotiating and implementing the PPP and also reimbursed £275m of bid costs to the winning bidders.^[31]

Supporters of the change claimed that the private sector would eliminate the inefficiencies of public-sector enterprises and take on the risks associated with running the network, while opponents said that the need to make profits would reduce the investment and public-service aspects of the Underground. The scheme was put in jeopardy when Metronet, responsible for two-thirds of the network, went into administration on 18 July 2007^[32][33] after costs for its projects spiralled out of control. The case for PPP was further weakened a year later when it emerged that Metronet's demise had cost the UK government £2 billion. The five private companies that made up the Metronet alliance had to pay £70m each towards paying off the debts acquired by the consortium. But under a deal struck with the government in 2003, the companies were protected from any further liability. The UK taxpayer therefore had to foot the rest of the bill. This undermined the argument that the PPP would place the risks involved in running the network into the hands of the private sector.^[34]

TfL took over the responsibilities of Metronet following its collapse. The Government made concerted efforts to find another private firm to fill the void, but none came forward. TfL and the Department for Transport have since agreed to allow TfL to continue operating the areas that were formerly the responsibility of Metronet. An independent panel will review TfL's investment programme. This left two-thirds of the Underground network completely under the control of TfL. The Secretary of State for Transport, at the time Lord Adonis, hinted that a separate arrangement might be made for the Bakerloo line at a later date.^[35]

Maintenance on the Jubilee, Northern and Piccadilly lines remained the responsibility of Tube Lines, although this too was not without controversy. The relationship between London Underground and Tube Lines deteriorated with disagreements over priorities, estimates and whether Tubes Lines had sufficient funds to meet its commitments.^[36] In late 2009 Tube Lines encountered a funding shortfall for their upgrades and requested that TfL provide an additional £1.75billion to cover the shortfall; TfL refused and referred the matter to the PPP arbiter, who stated that £400million should be provided.^[37] There had been many discussions over the future of the company in the second review period and it was announced on 7 May 2010 that TfL had agreed to buy the shares of Bechtel and Amey (Ferrovial) from Tube Lines for £310m.^[38] Combined with the takeover of Metronet, this means that the PPP is dead as all maintenance is now managed in-house by TfL.^[38]

Transport for London[link]

Westminster tube station and Big Ben clock tower

Transport for London (TfL) was created in 2000 as the integrated body responsible for London's transport system. It replaced London Regional Transport. It assumed control of London Underground Limited in July 2003.^[28]

TfL is part of the Greater London Authority and is constituted as a statutory corporation regulated under local government finance rules.^[39] It has three subsidiaries: London Transport Insurance (Guernsey) Ltd., the TfL Pension Fund Trustee Co. Ltd. and Transport Trading Ltd (TTL). TTL has six wholly owned subsidiaries, one of which is London Underground Limited.

The TfL Board is appointed by the Mayor of London. The Mayor also sets the structure and level of public transport fares in London. However the day-to-day running of the corporation is left to the Commissioner of Transport for London. The current Commissioner is Peter Hendy.^[40]

The Mayor is responsible for producing an integrated transport strategy for London and for consulting the GLA, TfL, local councils and others on the strategy. The Mayor is also responsible for setting TfL's budget. The GLA is consulted on the Mayor's transport strategy, and inspects and approves the Mayor's budget. It is able to summon the Mayor and senior staff to account for TfL's performance. London TravelWatch, a body appointed by and reporting to the Assembly, deals with complaints about transport in London.^[41]

Infrastructure[link]

Stations and lines[link]

The London Underground's 11 lines are divided into two classes: the subsurface routes and the deep-tube routes. The Circle, District, Hammersmith & City, and Metropolitan lines make up the subsurface class. The Bakerloo, Central, Jubilee, Northern, Piccadilly, Victoria and Waterloo & City lines are the deep-tube routes.

There was a twelfth line, a fifth subsurface route, the East London line, until 2007, when it closed for rebuilding work. It reopened as part of London Overground in April 2010.^[42]

The Underground serves 270 stations by rail. Fourteen Underground stations are outside Greater London, of which five (Amersham, Chalfont & Latimer, Chesham, and Chorleywood on the Metropolitan Line, and Epping on the Central Line), are beyond the M25 London Orbital motorway. Of the 32 London boroughs, six (Bexley, Bromley, Croydon, Kingston, Lewisham and Sutton) are not served by the Underground network, while Hackney has Old Street and Manor House only just inside its boundaries.

Zone 1 (central zone) of the Underground (and DLR) network in a geographically more accurate layout than the usual Tube map, using the same style

Underground trains come in two sizes, larger subsurface trains and smaller tube trains. A Metropolitan line A Stock train (left) passes a 1938 Stock train running a special service (right) near Croxley

The subsurface lines were dug by the cut-and-cover method, with the tracks running about 5 m (16 ft 5 in) below the surface. The deep-level or tube lines, bored using a tunnelling shield, run about 20 m (65 ft 7 in) below the surface (although this varies considerably), with each track in a separate tunnel. These tunnels can have a diameter as small as 3.56 m (11 ft 8 in), and the loading gauge is thus considerably smaller than on the subsurface lines. Lines of both types usually emerge on to the surface outside the central area.

While the tube lines are for the most part self-contained with a few exceptions, the subsurface lines are part of an interconnected network: each shares track with at least two other lines. The subsurface arrangement is similar to the New York City Subway, which also runs separate routes over shared tracks.

Rolling stock and electrification[link]

1996 Stock trains at Stratford Market Depot

The Underground uses rolling stock built between 1960 and the present. Stock on subsurface lines is identified by a letter (such as A Stock, used on the Metropolitan line), while tube stock is identified by the year in which it was designed (for example, 1996 Stock, used on the Jubilee line). All lines are worked by a single type of stock except the District line, which uses both C and D Stock. A new type of stock is currently being introduced for the subsurface lines – S stock, with the Metropolitan line A Stock being replaced first. In addition to the electric multiple units described above, there are engineering trains, such as ballast trains and brake vans, identified by a 1–3 letter prefix and then a number.

LUL has invited Alstom, Bombardier and Siemens to develop a new concept of lightweight, low-energy, semi-articulated train for the deep-level lines, provisionally called "Evo" (for 'evolution'). So far only Siemens has publicised an outline design, which would feature air-conditioning and would also have battery power enabling the train to run on to the next station if fourth-rail power were lost. It would have a lower floor and 11% higher passenger capacity than the present tube stock.^[44] There would be a weight saving of 30 tonnes, and the trains would be 17% more energy-efficient with air-conditioning included, or 30% more energy-efficient without it.^[45] The intention is that these new trains would eventually operate on the Bakerloo, Central, Piccadilly and Waterloo & City lines.^[46]

The Underground is one of the few networks in the world that uses a four-rail system. The additional rail carries the electrical return that on third-rail and overhead networks is provided by the running rails. The reason for this is that the return current, if allowed to flow through the running rails, would also tend to flow through the cast-iron tunnel segments. These were never designed to carry electrical currents and would suffer from galvanic corrosion if significant currents were allowed to flow through the joints. On the Underground, a top-contact third rail is beside the track, energised at +420 V DC and a top-contact fourth rail is centrally between the running rails, at −210 V DC, which combine to provide a traction voltage of 630 V DC.

In cases where the lines are shared with main-line trains which use a three-rail system (usually above ground and not within cast iron tunnel segments), the third rail is set at +630 V and the fourth rail at 0 V DC.^[47]

Planned improvements and expansions[link]

The Crossrail line will provide a new east-west link and will be integrated with the tube network, but will not be part of it

Each line is being upgraded to improve capacity and reliability, with new computerised signalling, automatic train operation (ATO), track replacement, station refurbishment and, where needed, new rolling stock.^[48] The four subsurface lines are currently being upgraded to a new radio-based CBTC signalling system which will permit to reduce headways and increase transport capacity.^[49]

A trial of mobile phone coverage on the Waterloo & City line^[50] determined that coverage would be appropriate for the entire network, and it is hoped to have the service installed in time for the 2012 Olympics.^[51] Mayor of London Boris Johnson revealed the plans would be funded through investment by the five main UK mobile networks: Vodafone, Orange, T-Mobile, 3 and O₂.^[51]

In summer, temperatures on parts of the Underground can become uncomfortable due to its deep and poorly ventilated tube tunnels; temperatures as high as 47 °C (117 °F) were reported in the 2006 European heat wave.^[52] A trial of a groundwater cooling system in Victoria station took place in 2006 and 2007 to determine whether such a system would be feasible and effective in widespread use for cooling the Underground. There are posters on the Underground network advising passengers to carry a bottle of water to help keep cool.^[53] The new S Stock trains currently being introduced on the Metropolitan line, and due to be introduced later on the Circle, District and Hammersmith & City lines, do have air-conditioning.^[54]

Although not part of London Underground, the Crossrail scheme is planned to provide a new route across central London by 2018, integrated with the tube network.^[55] The long-proposed Chelsea–Hackney line, which would not be built until after Crossrail, may become part of the London Underground. It would give the network a new north-east to south cross-London line, with many interchanges with other lines, to relieve overcrowding on other lines. However it is still on the drawing-board and might become part of either the London Underground network or London Overground (part of the National Rail network).

The Croxley Rail Link project involves diverting the Metropolitan line Watford branch to Watford Junction station along a disused railway track. The project was approved by the Government on 14 December 2011.^[56] Construction work is expected to start in June 2014 and be finished by January 2016.^[57]

Boris Johnson has suggested extending the Bakerloo Line to Lewisham, Catford and Hayes as South London lacks Underground lines (instead having a suburban rail network).^[58]

There have also been proposals to reorganise the sub-surface lines,^[59][60] to split the Northern Line and to extend its Charing Cross branch to Battersea,^[61][62] although both of these are dependent upon other upgrades being completed first. The plan for a Northern line extension to Battersea has been given planning permission by the London Borough of Wandsworth.^[63] The extension to Battersea would be privately funded as part of the Battersea Power station development, involving a major regeneration of the Nine Elms and Battersea areas.^[64]

The London Borough of Hillingdon has proposed that the Central Line be extended from West Ruislip to Uxbridge via Ickenham. The extension would cut traffic on the A40 in the area and could be complete by 2021. The extension would run along existing track between Ickenham and Uxbridge, but the extension would rely on signalling system upgrades which may take until 2017 to be put in place.^[65]

Travelling[link]

Ticketing[link]

The Oyster card, a contactless smart card used across the London transport system

London Authorities' Freedom Pass (disabled version)

The Underground uses TfL's Travelcard zonal fare system to calculate fares. Greater London is divided into 6 zones; Zone 1 is the most central, with a boundary just beyond the Circle line, and Zone 6 is the outermost and includes London Heathrow Airport. Stations on the Metropolitan line outside Greater London are in Zones 7–9.^[66] There are staffed ticket offices, some open for limited periods only, and ticket machines usable at any time. Some ticket machines accept coins, notes and credit cards, some accept coins only, and some accept cards only.

In 2003, TfL introduced the Oyster card, a smartcard with an embedded contactless RFID chip, which travellers can charge up with credit and use to pay for travel. It can also be loaded with Travelcards. Like a paper Travelcard, it can be used on the Underground, the Overground, buses, trams, the Docklands Light Railway, and National Rail services within London. TfL encourages passengers to use Oyster cards instead of Travelcards or cash by implementing significant price differences, so travel by Oyster card is significantly cheaper.^[67]

Since GLC days there has been a concessionary fare scheme for disabled London residents and those aged over 60. Since 2006, the scheme has been called the "Freedom Pass" and allows for free travel on TfL-operated routes at all times. It is also valid on National Rail services within London, except between 04:30 and 09:30 on Monday to Fridays on some lines. The pass itself is, in effect, a free Oyster card, though it does not bear that name. Since 2010, the Freedom Pass has included an embedded holder's photograph; it lasts five years between renewals.^[68]

Penalty fares and fare evasion[link]

In addition to automatic and staffed ticket gates, the Underground is patrolled by both uniformed and plain-clothes ticket inspectors with hand-held Oyster card readers. Passengers travelling without a ticket valid for their entire journey must pay a penalty fare of £80 (or £40 if paid within 21 days) and can be prosecuted for fare evasion under the Regulation of Railways Act 1889, under which they are subject to a fine of up to £1,000 or three months' imprisonment. Oyster card pre-pay users who have failed to touch in at the start of their journey (or have touched in, but not out at the end of the journey) are charged the maximum cash fare, currently £6 in peak hours or £4.30 off peak. In addition, Oyster card users who have failed to touch in at the start of their journey and who are detected mid-journey (e.g. on a train) by an Inspector are now liable to a penalty fare of £50, reduced to £25 if paid within 21 days. No maximum charge is applied at their destination as the inspector will apply an 'exit token' to their card.

While the Conditions of Carriage require period Travelcard holders to touch in and touch out at the start and end of their journey (which is usually necessary to open automatic ticket gates), Oyster card users with a valid period Travelcard covering their entire journey are not liable to pay a penalty fare when they have not touched in. Neither the Conditions of Carriage nor Schedule 17 of the Greater London Authority Act 1999, which states how and when penalty fares can be issued, allow the issue of a penalty fare to a traveller who had already paid the correct fare for their journey.

Hours of operation[link]

The Underground does not run 24 hours a day (except at New Year and major public events – such as the Queen's Golden Jubilee in 2002 and the Opening and Closing Ceremonies of the London Olympics in 2012) because most lines have only two tracks (one in each direction) and therefore need to close at night for cleaning and planned maintenance work. First trains start operating from approximately 04:45, generally for shorter journeys such as the Piccadilly line's Osterley-Heathrow only rather than the full length of the line, with the remainder operating by 05:30, running until around 01:00. Unlike systems such as the New York City Subway, few segments of the Underground have third or fourth tracks that allow trains to be routed around maintenance sites. Recently, greater use has been made of weekend closures of parts of the system for scheduled engineering work. Also, the Underground runs limited service on Christmas Eve (with some lines closing early) and does not operate on Christmas Day, except for the shuttle to Heathrow Airport. A limited service is provided on Boxing Day.

Accessibility[link]

King's Cross St. Pancras tube station is a massive interchange station linking two mainline rail terminals. It is also one of the few fully step-free accessible stations on the network.

The S Stock, the newest rolling stock on the Underground, is designed to be more accessible, having dedicated wheel chair areas and lower platforms.

Accessibility by people with mobility problems was not considered when most of the system was built, and most older stations are inaccessible to disabled people. More recent stations were designed for accessibility, but retrofitting accessibility features to old stations is at best prohibitively expensive and technically extremely difficult, and often impossible. Even when there are already escalators or lifts, there are often steps between the lift or escalator landings and the platforms.

Most stations on the surface have at least a short flight of stairs to gain access from street level, and the great majority of below-ground stations require use of stairs or some of the system's 410 escalators. There are also some lengthy walks and further flights of steps required to gain access to platforms. The emergency stairs at Covent Garden station have 193 steps to reach the exit (equivalent to climbing to the top of a 15-floor building),^[69] so passengers are advised to use the lifts as climbing the steps can be dangerous.

TfL produces a map indicating which stations are accessible, and since 2004 line maps indicate with a wheelchair symbol those stations that provide step-free access from street level. Step height from platform to train is up to 300 mm (11.8 in), and there can be a large gap between the train and curved platforms. Only the Jubilee Line Extension is completely accessible.

TfL plans that by 2020 there should be a network of over 100 fully accessible stations, consisting of those recently built or rebuilt, and a handful of suburban stations that happen to have level access, along with selected 'key stations', which will be rebuilt. These key stations have been chosen due to high usage, interchange potential, and geographic spread, so that up to 75% of journeys will be achievable step-free.

Escalators[link]

The Angel tube station escalator – the third longest escalator in Western Europe

The escalators in Underground stations include some of the longest in Europe and all are custom-built. The longest escalator is at Angel station, 60 m (197 ft) long, with a vertical rise of 27.5 m (90 ft).^[8] They run 20 hours a day, 364 days a year, with 95% of them operational at any one time and can cope with 13,000 passengers per hour.

Signs ask people using escalators on the Underground to stand on the right-hand side so as not to obstruct those in a hurry walking past them on the left. The explanation for overtaking on the left, although road traffic in Britain overtakes on the right, is that, unlike modern "comb" escalators, where the end of the moving stairway is at right angles to the direction of travel, older "shunt" escalators ended with a diagonal so that the stairway finished sooner for the right foot than for the left. The idea was to allow passengers to keep their left foot on a moving stairway as they stepped off with their right. Passengers who chose not to walk down the escalators were asked to stand on the right so that anyone wishing to overtake them at the end would be able to take advantage of the extra section of moving stairway.^[70]

Delays and overcrowding[link]

Overcrowding is a daily problem on the tube system.

According to statistics obtained under the Freedom of Information Act, the average commuter on the Metropolitan line in 2006 wasted three days, 10 hours and 25 minutes due to delays.^[71] Between 17 September 2006 and 14 October 2006, figures show that 211 train services were delayed by more than 15 minutes.^[72] Passengers are entitled to a refund if their journey is delayed by 15 minutes or more due to circumstances within the control of TfL.^[73] However in 2010, only 330,000 passengers of a potential 11 million Tube passengers claimed compensation for delays.^[74] That translates to only £2m out of the £34 million owed to commuters. Following the UK government's move towards opening up its data, a number of new services such as TubeTap iPhone app have been developed to help Londoners claim their refund more efficiently.^[75] Planned engineering work affect 82.3% of passengers at least once a month.^[76]

Overcrowding on the Underground has been of concern for years and is very much the norm for most commuters during the morning and evening rush hours, with 95.2% of passengers being regularly affected by it.^[76] Stations which have a particular problem include Camden Town station, Chancery Lane and Covent Garden, which accordingly have access restrictions at certain times.^[77] Restrictions are introduced at other stations when necessary. Several stations have been rebuilt to deal with overcrowding: Clapham Common and Clapham North on the Northern line are the last remaining stations with a single narrow platform with tracks on both sides. On particularly busy occasions, such as football matches, British Transport Police may be present to help with crowd management.

Some stations are closed or are made exit-only stations due to overcrowding in peak periods. At other times trains simply do not stop at the overcrowded station and go on to the next closest station, in places where there is another station within walking distance. Overcrowding can also be limited by temporarily disallowing passengers from passing through ticket gates to the platforms at some stations.

In 2009, temperatures in the deep tunnels were recorded as reaching as high as 32°C,^[78] and this is combined with poor air quality, which a 2003 study claimed was 73 times worse than at street level, with twenty minutes on the Northern Line having "the same effect as smoking a cigarette".^[79] According to a 2003 House of Commons report,^[80] commuters faced a "daily trauma" and were forced to travel in "intolerable conditions".

Safety[link]

Accidents on the Underground network, which carries around a billion passengers a year, are rare. There is one fatal accident for every 300 million journeys.^[81] There are several safety warnings given to passengers, such as the 'mind the gap' announcement and the frequent announcements to passengers to keep behind the yellow line. Relatively few accidents are caused by overcrowding on the platforms: staff monitor platforms and passageways at busy times and prevent people entering overcrowded areas.

Most fatalities on the network are suicides. Most platforms at deep tube stations have pits beneath the track. These were originally constructed to aid drainage of water from the platforms, but they also help prevent death or serious injury when a passenger falls or jumps in front of a train.^[82]

Design and the arts[link]

TfL's Tube map and "roundel" logo are instantly recognisable by any Londoner, almost any Briton and many people around the world. It has become a major pop culture symbol.^[83]

TfL licenses the sale of clothing and other accessories featuring its graphic elements and it takes legal action against unauthorised use of its trademarks and of the Tube map. Nevertheless, unauthorised copies of the logo continue to crop up worldwide.

Map[link]

The original maps were often city maps with the lines superimposed, but as well as being visually complex, this produced problems of space, as central stations were far closer together than outlying ones. The modern stylised Tube map evolved from a design by electrical engineer Harry Beck in 1933.^[84] It is characterised by a schematic non-geographical layout (thought to have been based on circuit diagrams) and the use of colour coding for lines. The map is now considered a design classic; virtually every major urban rail system in the world now has a similar map and many bus companies have also adopted the concept. There are many references in culture to the map, including parodies of it using different station-names – an example being the official cover art used on tube maps during 2010.^[85] Such references also occur in London advertisements for unrelated products and services.

Typography[link]

Edward Johnston designed TfL's distinctive sans-serif typeface in 1916. The typeface is still in use today although substantially modified in 1979 by Eiichi Kono at Banks & Miles to produce "New Johnston". It is noted for the curl at the bottom of the minuscule (lower case) l, which other sans-serif typefaces have discarded, and for the diamond-shaped tittle on the lower case i and j, whose shape also appears in the full stop, and is the origin of other punctuation marks in the face. TfL owns the copyright to and exercises control over the New Johnston typeface, but a close approximation of the face exists in the TrueType computer font Paddington and the Gill Sans typeface also takes inspiration from Johnston.

Roundel[link]

The London Underground roundel, seen here at Piccadilly Circus

The origins of the roundel, in earlier years known as the 'bulls-eye' or 'target', are obscure. While the first use of a roundel in a London transport context was the 19th-century symbol of the London General Omnibus Company – a wheel with a bar across the centre bearing the word GENERAL – its use on the Underground stems from the decision in 1908 to find a more obvious way of highlighting station names on platforms. The red circle with blue name bar was quickly adopted, with the word "UNDERGROUND" across the bar, as an early corporate identity.^[86] The logo was modified by Edward Johnston in 1919.

Each station displays the Underground roundel, often containing the station's name in the central bar, at entrances and repeatedly along the platform, so that the name can easily be seen by passengers on arriving trains.

The roundel has been used for buses and the tube for many years and, since TfL took control, it has been applied to other transport types (taxi, tram, DLR etc.) in different colour pairs.

The 100th anniversary of the roundel was celebrated by TfL commissioning 100 artists to produce works that celebrate the design.^[87]

Contribution to arts[link]

Silhouette of Sherlock Holmes at Baker Street tube station

The Underground currently sponsors and contributes to the arts via its Art on the Underground and Poems on the Underground projects. Poster and billboard space (and in the case of Gloucester Road tube station, an entire disused platform) is given over to artwork and poetry to "create an environment for positive impact and to enhance and enrich the journeys of ... passengers".

Its artistic legacy includes the employment, since the 1920s, of many well-known graphic designers, illustrators and artists for its own publicity posters. Designers who produced work for the Underground in the 1920s and 1930s include Man Ray, Edward McKnight Kauffer, William Kermode and Fougasse. In recent years, the Underground has commissioned work from leading artists including R. B. Kitaj, John Bellany and Howard Hodgkin.

In architecture, Leslie Green established a house style for the new stations built in the first decade of the 20th century for the Bakerloo, Piccadilly and Northern lines which included individual Edwardian tile patterns on platform walls.^[88] In the 1920s and 1930s, Charles Holden designed a series of modernist and art-deco stations for which the Underground remains famous. Holden's design for the Underground's headquarters building at 55 Broadway included avant-garde sculptures by Jacob Epstein, Eric Gill and Henry Moore (his first public commission). Misha Black was appointed design consultant for the 1960s Victoria Line, contributing to the line's uniform look,^[89] while the 1990s extension of the Jubilee line featured stations designed by leading architects such as Norman Foster, Michael Hopkins, Will Alsop and Ian Ritchie. These architects were commissioned by Roland Paoletti, chief architect for the Jubilee Line Extension (JLE).

Many stations also feature unique interior designs to help passenger identification. Often, these have themes of local significance. Tiling at Baker Street incorporates repetitions of Sherlock Holmes's silhouette. Tottenham Court Road features semi-abstract mosaics by Eduardo Paolozzi representing the local music industry at Denmark Street. Northern line platforms at Charing Cross feature murals by David Gentleman of the construction of Charing Cross itself.

In popular culture[link]

Model of a London Underground carriage in Miniland at Legoland Windsor

The Underground (including several fictitious stations^[90]) has been featured in many movies and television shows, including Sliding Doors, An American Werewolf in London, Creep, Tube Tales and Neverwhere. The London Underground Film Office received over 200 requests to film in 2000.^[91] The Underground has also featured in music such as The Jam's "Down in the Tube Station at Midnight" and in literature such as the graphic novel V for Vendetta. Popular legends about the Underground being haunted persist to this day.^[92]

London Underground voiceover artiste Emma Clarke has recorded a number of spoof announcements, available on her personal website.^[93]

The announcement "mind the gap", heard when trains stop at certain platforms, has also become a well known catchphrase.^{[citation needed]}

Call of Duty: Modern Warfare 3 has a level named Mind the Gap where most of the level takes place between the dockyards and Westminster while the player and a team of SAS attempt to take down cargo being shipped using London Underground.^{[citation needed]}

The London Underground map serves as a playing field for the conceptual game of Mornington Crescent (which is named after a station on the Northern Line) and the board game The London Game.

[edit] The Tube

The Tube is a BBC Two television documentary which looks into the life of those who work and travel on London Underground. The show first aired on 20 February 2012. The show was first announced by the director of BBC Two in October 2011 and follows various London Underground employees in their day-to-day roles.

Notable people[link]

• Frank Pick, Managing Director of the Underground Group from 1928 and Chief Executive of the London Passenger Transport Board from its creation in 1933 until 1940.
• Lord Ashfield, chairman of the Underground Electric Railways Company of London (UERL) from 1910 to 1933 and chairman of the London Passenger Transport Board (LPTB) from 1933 to 1947.
• Edward Watkin, responsible for the building of the Manchester Sheffield & Lincolnshire Railway's "London Extension" during the 1890s, which was the last main line to be constructed into London.
• Edgar Speyer, chairman of the Underground Electric Railways Company of London (UERL, forerunner of the London Underground) from 1906 to 1915, a period during which the company opened three underground railway lines, electrified a fourth and took over two more.
• James Henry Greathead, who helped with the Tower Subway, and became resident engineer on the Hammersmith extension railway and the Richmond extension of the Metropolitan District Railway, a post which he held for four years.
• Charles Pearson, who published a pamphlet in 1845 calling for the construction of an underground railway through the Fleet valley to Farringdon. The proposed railway would have been an atmospheric railway with trains pushed through tunnels by compressed air. Although the proposal was ridiculed and came to nothing (and would almost certainly have failed if it had been built, due to the shortcomings of the technology proposed), Pearson continued to lobby for a variety of railway schemes throughout the 1840s and 1850s. In 1846, Pearson proposed with the support of the City Corporation a central railway station for London located in Farringdon that was estimated to cost £1 million (approximately £71.7 million today).
• Daniel Gooch, who designed and built 22 outside-cylinder 2-4-0 locomotives for the line in 1863.
• Charles Yerkes, an American tycoon with experience of operating electric tramways in Chicago. He was also an expert in arranging the complex financial structures necessary to raise the capital the railway companies needed. In 1900, he bought the powers of the CCE&HR company. The following year he secured effective control of the District with a view to its electrification.

Selected facts[link]

• Longest journey without changing trains – 34.1 miles (54.9 km), from West Ruislip to Epping on the Central line taking 1 hour 28 minutes.^[94]
• Longest distance between stations – 3.89 miles (6.26 km), between Chalfont & Latimer and Chesham on the Metropolitan line.^[94]
• Shortest distance between stations – 0.16 miles (0.26 km), between Leicester Square and Covent Garden on the Piccadilly line.^[94]
• Shortest escalator – 13 feet (4.0 m), at Stratford station.^[94]
• Longest escalator – 197 feet (60 m), at Angel station.^[94]
• Deepest lift shaft – 181 feet (55 m), at Hampstead station.^[94]
• Deepest station – 192 feet (59 m) below street level, at Hampstead station.^[94]
• Shallowest deep-level station – 26 feet (7.9 m), at Redbridge station.^[95]
• Highest station – 490 feet (150 m) above sea level, at Amersham.^[94]
• Furthest outpost – 27 miles (43 km), Amersham station.^[94]
• Line serving the most stations – District line, serving 60 stations.^[94]
• Line serving the fewest stations – Waterloo & City line, serving 2 stations.^[94]
• Busiest station – Waterloo station with 82 million passengers a year.^[94]
• Highest point above ground level – 60 feet (18 m), Dollis Brook Viaduct on the Northern line's Mill Hill East branch.^[94]
• Fastest Tube Challenge journey to visit to all London Underground stations – 14 hours, and 17 minutes.^{[citation needed]}

See also[link]

London Transport portal

	Book: London
Wikipedia books are collections of articles that can be downloaded or ordered in print.

• Timeline of the London Underground
• List of the busiest London Underground stations

References[link]