The London Underground is a public transport network, composed of electrified railways that run underground in tunnels in central London and above ground in the London suburbs. It is usually called either the Underground or the Tube by Londoners. It is the oldest city underground network in the world.

Table of contents
1 Background
2 Layout
3 History
4 Tickets
5 Station Access
6 Safety
7 Iconography
8 The Future
9 The Tube in fiction
10 See also


Since 2003 the Tube has been part of Transport for London (TfL), who also schedule and let contracts for the famous red double-decker buses. Previously London Transport was the holding company for London Underground.

Today there are 275 stations and over 408 km of active lines, with 3 million passenger journeys made each day (927 million journeys made 1999-2000).

Lines on the Underground can be classified into two types: sub-surface and deep level. The sub-surface lines were dug by the cut-and-cover method, with the tracks running about 5 metres below the surface. Trains on the sub-surface lines have the same loading gauge as British mainline trains. The deep-level or "tube" lines, bored using a tunnelling shield, run about 20 metres below the surface (although this varies considerably), with each track running in a separate tunnel lined with cast-iron rings. These tunnels can have a diameter as low as 3.56m (11ft 8.25in) and the loading gauge is thus considerably smaller than on the sub-surface lines, though standard gauge track is used. Lines of both types usually emerge onto the surface outside the central area, the exceptions being the Victoria Line which is in tunnel for its entire length, and the Waterloo and City which, being very short, has no non-central part and no surface line.


The table below describes each of the lines, giving the colour used to represent the line on the ubiquitous Tube maps, the date of opening and the type of tunnelling used.

Line NameMap colourYear of openingTypeNotes
Bakerloo Line
1906Deep level
Central Line
1900Deep level
Circle Line
District Line
East London Line
Hammersmith & City Line
Jubilee Line
1979Deep level
Metropolitan Line
Northern Line
1907 (part)Deep level4
Piccadilly Line
Dark blue
1906Deep level
Victoria Line
Light blue
1969Deep level
Waterloo and City Line
1898Deep level5
1The Circle Line became known as such in 1949. The Circle line was not built as a separate line, but was instead created by joining parts of the District and Metropolitan Lines.
2Originally called the Metropolitan District Railway
3aOriginally a separate line operated by a consortium of companies including the Metropolitan. The line was owned by London Underground from 1948 but British Railways goods trains continued to run on it until 1966. It was for many years regarded as a branch of the Metropolitan Line, and was shown on the map as a purple and white striped line. The line gained its own identity in the late 1980s.
3bOriginally part of the Metropolitan Line, the line became known as the Hammersmith & City Line in 1990.
4The busiest line on the system, with two branches in central London.
5Came under control of London Transport in 1994.

The Piccadilly Line now runs to Heathrow Airport. Although it is slow (about 45 minutes) and often crowded, it is the cheapest way to travel directly between Heathrow and the city centre.

The Tube interchanges with the Docklands Light Railway (DLR) at several stations, including Bank, Canary Wharf and Stratford, and with the Croydon Tramlink system at Wimbledon. The Tube interchanges with international Eurostar trains at Waterloo.

The lack of lines in the south of the city is because of the geology of that area, the region almost being one large aquifer. This is made up for, however, by a large number of suburban rail services run by the South West Trains, South Central and Connex franchise holders (see British railway system).


As the oldest and one of the most complicated rapid transit systems in the world, the London Underground has a long history.

The first half of the 19th century saw rapid development in train services to London, but most mainline termini were constructed a long way away from the central business district to avoid damage to historic buildings. As a result, reliance on buses increased until London was gridlocked. The solution came in the form of yet another railway. In 1854 it was decided that the Metropolitan Railway Company would be allowed to build a short stretch of underground railway between Paddington and Farringdon. This would link the mainline termini of King's Cross, St. Pancras, Euston and Paddington to a point near the edge of the City of London. The relatively simple cut-and-cover method was used, because deep-level tunnel construction methods were not sufficiently advanced to construct anything more than covered trenches. This first part of the Metropolitan Railway was opened in 1863 using steam locomotives to haul trains, which meant that ventilation shafts had to be built at regular intervals.

Expansion was rapid. The Metropolitan quickly branched out into the suburbs, even creating whole villages from nothing in a region of countryside which came to be known as "Metroland". The railway bought up extra land adjacent to the railway and built houses in a spectacularly practical example of demand creation and by 1880 the 'Met' was carrying 40 million passengers a year.

Meanwhile, a second railway company began construction further south. The Metropolitan District Railway first opened a stretch from Westminster to South Kensington in 1868, taking advantage of the construction of the Thames embankment to expand towards the city, reaching Tower Hill and linking the termini of Victoria, Charing Cross, Blackfriars, Cannon Street and Fenchurch Street. Having conquered the city, the District Railway turned its attention to commuters even more so than the Metropolitan Railway had, reaching Wimbledon, Richmond and Ealing.

Although the Circle Line didn't get its own identity until 1949, the "District" and the "Metropolitan" had linked up with each other to provide an "Inner Circle" service starting in 1884.

Advances in deep-level tunnel design came thick and fast. Tunnelling shields allowed stable tunnels to be constructed deep underground, and the world's first underground tube railway was the Tower Subway beneath the River Thames south of Tower Hill in 1870. While this was soon discontinued as a rail service, better shields and electric locomotive traction appealed to engineers for more ambitious schemes.

The result was the City and South London Railway, which linked King William Street (close to today's Monument Station) and Stockwell. The ride was unpleasantly rough and the lack of windows seemed to have a detrimental psychological effect. However, people learned from these mistakes and over the next 25 years six independent deep-level lines were built.

The presence of six independent operators running different Tube lines was inconvenient. In many places passengers had to walk some distance above ground to change between lines. Also, the costs associated with running such a system were heavy, and as a result many companies looked to financiers who could give them the money they needed to expand into the lucrative suburbs.

One such financier was Charles Yerkes, an American tycoon whose companies (first the Metropolitan District Traction Company, then Underground Electric Railways of London) initially took over the District, Picadilly and Bakerloo lines. The Underground Group, as this second company was known, gradually absorbed the rest of the tube lines, save the Metropolitan and the Waterloo & City (which remained separate until 1994). The company also owned many tram lines and proceeded to buy the London General Omnibus Company, creating an organization colloquially known as the Combine. In 1933, a public corporation called the London Passenger Transport Board was created. The Underground Group, the Metropolitan line and all the independent bus and tram lines were placed under the Board, an organization which approximateed the scope of the current Transport for London.

Between the wars, expansion took place at a rapid pace, driving the Northern and Bakerloo Lines out into the suburbs of northern London. Architect Charles Holden's memorable station designs have brightened the commuter's journey both on these lines and elsewhere with a style which still looks fresh today.

World War II

The outbreak of World War II, and especially The Blitz, led to the use of many Tube stations as air-raid shelters. They were particularly suited to this purpose, but sadly a small number of horrific accidents occurred, notably at Bethnal Green. Other stations and sections of line were given other uses:

  • A remote stretch of the Central Line was turned into an underground aeroplane factory.
  • The closed Brompton Road station was used as an anti-aircraft control centre.
  • The closed Down Street station was used by Winston Churchill until the Cabinet War Rooms were built, after which it was used by the Emergency Railway Committee.

Post War Developments

Following the war, travel congestion continued to rise. The construction of the carefully planned Victoria Line on a diagonal northeast-southwest alignment beneath central London attracted much of the extra traffic caused by expansion after the war. It was designed so that almost all of the stations along its length allowed interchange with other lines, and it was the first underground line to use automatic train operation (ATO).

The Jubilee Line was named in honour of Queen Elizabeth's Silver Jubilee in 1977, but did not open until two years later. During the 1990s it was extended through the Docklands to Stratford in East London. The stations on the Jubilee Line Extension are particularly spacious and stylish, each designed by a leading architect. London Underground states that North Greenwich station, for example, "is large enough to contain 3,000 double-decker buses or an ocean liner the size of the Queen Mary within its walls." Canary Wharf station is larger in volume than 1 Canada Square, one of the huge towers that dominates the Docklands area. All platforms west of Canning Town incorporate automated platform-edge doors that help to minimise the wind resistance of the train and prevent suicides. These modern stations include lifts (US: elevators) to ease access to all parts of the station complex.

An increasing problem for the system is flooding. Since the 1960s, the ground water of London has been rising, after the closing of industries such as breweries and paper mills that had previously extracted large volumes of water. By mid 2001 London Underground was pumping 30,000 cubic metres of water out of its tunnels each day.

Until the completion of the Thames flood barrier in 1986, there was also a strong danger of flooding from the Thames itself. A series of floodgates were erected in the tunnels such that they would seal the affected sections of tunnel closed, allowing services to continue to run elsewhere on the line. The floodgates were no longer necessary once the Thames flood barrier came into service, but they remain in place and are tested three times a year.


Transport for London (and local National Rail franchisees) use a zonal pricing scheme where zone 1 is the most central, with a boundary just outside the Circle Line. After number 6, the zones are named A, B, C and D; zone D is the most remote and consists of Amersham and Chesham out in the Chiltern Hills on the Metropolitan Line. These lettered zones cater for the rural extremities of the tube and do not encircle the capital. Buses treat zones 4, 5 and 6 as a combined zone 4.

In general, the more zones travelled through, the higher the fare. Journeys through zone 1 are more expensive than those only involving outer zones. The zone system works well because most of the stations where lines cross are in zone 1, meaning that most journeys over similar distances will cost the same.

There are assistance booths open for limited periods and ticket machines usable at any time. The machines will accept coins and fresh English paper money — though not Northern Irish or Scottish notes — and usually give change. LT and the Docklands Light Railway have recently introduced credit and debit card ticket machines across their networks. A small number of cash machines dispensing all-zone bus passes have appeared.

In 2003 London Underground launched the Oyster Card, a proximity card that a traveller swipes over a reader on the automatic gates rather than feeding it through a card ticket reader. Unlike the card tickets, the Oyster Card is not disposable, but intended to be topped up at the ticket machines.

London Transport also sell daily, weekend, weekly, monthly and annual "LT cards", allowing unlimited rides in one or more zones on buses or on the London Underground; these are a good deal for commuters and anyone else who rides the trains or buses daily. Travelcards are similar, although they also permit travel on National Rail. Daily Travelcards are only sold from machines after 9:30 am, but a peak hour inclusive version is available at a much higher price. Many shops, usually newsagents, sell bus passes and Travelcards; these are identified by a "Pass Agent" sign, usually in a door panel or front window. A day pass is valid until 4:30 am the next morning. Passes can be bought from these agents during a day prior to travel.

Station Access

Not all Underground stations are accessible by people with mobility problems. Many have some of the 408 escalators and 112 lifts (elevators), but not all of them. New stations are designed for accessibility, but retrofitting accessibility features to old stations is considered prohibitively expensive.

The escalators in London Underground stations are both an asset and a liability. They are among the longest escalators in Europe and all are custom-built for each station. Because of their age and heavy usage, they tend to break down rather frequently, causing long delays at stations.

London Transport now produces a map specifically indicating which stations are accessible. However, step height from platform to train is often as high as 20 cm on older lines, and there can be a large gap between the train and some curving platforms. Only the Jubilee Line Extension is completely usable by the unassisted wheelchair-using traveller.


The London Underground has an excellent passenger safety record. Suicides are unfortunately common, at roughly one per week across the network. Surprisingly few accidents are caused by overcrowding on the platforms; one explanation suggested for this — presumably by people who have never actually visited London or the Tube — is that Londoners are too polite to push!

For its employees, however, the record is less good. In January 2002 London Underground was fined 225,000 for breaching safety standards for workers. In court the judge said the company was "sacrificing safety" to keep the trains running "at all costs." He continued that the company, "despite the lip service they paid to health and safety issues, fell lamentably short of the proper safety standards and, objectively, simply ignored their obligations in this respect." Workers had been ordered to work in the rain, in the dark, while the track current was still switched on. (Source: BBC News)

The worst recent incident was a fire at King's Cross station on November 18, 1987, caused by a smouldering cigarette stub falling onto a wooden-tread escalator panel. Thirty-one people died in the fire, which prompted the phasing out of wooden escalators and the prohibition of smoking throughout the system.


The London Underground Roundel at
Westminster ()

London Transport's logo (shown above) and tube map are instantly recognizable by any Londoner, almost any Briton, and many people around the world.

The logo, as well as London Transport's distinctive sans-serif typeface, were designed by Edward Johnston, the former in 1913, the latter in 1916. Much of the reason for the widespread recognition of the London Transport logo is its ubiquitous usage on London Transport documents and signage. It is used for all tube station signs (where the station name appears on the horizontal bar), for example, as well as on in-carriage maps.

Tube Map

The tube map was designed by Harry Beck in 1931. See Tube map for an in-depth analysis of its history and its topological nature.

London Transport is known for taking legal action against unauthorized use of its trademarks, in spite of which unauthorized copies of the logo continue to crop up worldwide.

The Future


The London Underground is currently part way through partial privatisation, the system's maintenance being taken over by two Infracos (Infrastructure Companies): Metronet and Tube Lines. It has been decided that Metronet will maintain the Bakerloo, Central, Victoria, the Waterloo & City, Circle, District, East London, Hammersmith & City and Metropolitan Lines. Tube Lines will handle the remainder: the Jubilee, Northern and Piccadilly Lines.

The aim of this "Public-Private Partnership" (PPP) is to accelerate investment in the sadly neglected aspects of the London Underground, commissioning new trains and installing safety features such as ATP, automatic train protection. The Mayor of London, Ken Livingstone, is sceptical about the practicality of the PPP plan. However, he has dropped a legal challenge against PPP, and refurbishment works are expected to be carried out from end 2002 onwards.


Plans are underway to extend the East London Line to both the North and the South; to the North, Shoreditch station will be abandoned, and, in a move that will bring the Underground to Hackney for the first time, the line will run on the old Broad Street viaduct to Hoxton, then to Highbury & Islington station to connect with the Victoria Line. Another branch may run on the same tracks as the North London Line to Willesden Junction. To the South, two branches are planned, running to Croydon and Wimbledon. These will transform the line from a small stub in the network to a major transport artery.


In the summer weather, temperatures on the Tube can become very uncomfortable for passengers. Normal air conditioning has been ruled out becase of the lack of height to intall units on trains and the problems of dipersing the heat generated. Heat pumps were proposed several years ago to overcome this, and following a successful demonstration in 2001 funds were given to the School of Engineering at London's South Bank University to develop a prototype; work began in April 2002. A cash reward of 100,000 pounds was offered by the Mayor of London in 2003 for a solution to the problem.

Underground stations

London Underground currently serves 275 stations, which are listed, along with DLR stations, at List of London Underground stations. Stations formerly served by the Underground or its predecessor companies can be found at List of closed London Underground stations.

The Tube in fiction

(Please add to this list.)

See also

External Links