How every fact on this site was checked
120 facts. Each one is in our own words, each one has a source, and each one was checked against that source on 10 November 2026.
How we check
We read each source and wrote each fact in our own words. Our build stores the text of every source page, and for each fact it checks that the key words and figures, the “checks” in the table, really appear on the source page. If any check fails, the site does not build. Where good sources disagree, we show each version in a “Sources differ” box rather than picking one. Anything that is our own reading, rather than a sourced fact, is labelled Our opinion. The drawings are our own and simplified.
Some pages would not load for our checker directly. For those we read the Internet Archive’s saved copy of the same page, and the link still goes to the original.
Known disagreements
- Length of the first line. 5.6km (London Transport Museum, Metropolitan line page), three miles (London Transport Museum, Victorian transport page), or 3.75 miles (6km) authorised by Parliament (Britannica).
- Stations on the first line. Seven stations, both ends included (London Transport Museum), or six intermediate stations (Transport for London).
- Size today. 11 lines, 402km and 272 stations (London Transport Museum; TfL gives 272 stations and 11 lines), or about 400km and some 270 stations at the start of the 21st century (Britannica).
What we left out
- Figures for the size of the network change. We give each as the named source states it, on the date we checked.
- Our line chart shows when the first part of each of today’s lines opened; several lines took their present names later.
- We do not show Harry Beck’s map itself, which is still in copyright; our drawing is an illustration of his idea on an invented network.
- Conversions between miles and kilometres in our own text are ours; the sourced figures are as each source gives them.
The log
| # | Fact | Source | Checks |
|---|---|---|---|
| 1 | The world’s first underground railway opened in London in 1863, to ease the congestion in the streets. | London Transport Museum: A very short history of the Underground | 1 passed |
| 2 | The first section of the Metropolitan Railway opened from Paddington to Farringdon on 10 January 1863. | London Transport Museum: The world’s first underground | 1 passed |
| 3 | The Metropolitan line is the oldest underground railway in the world, named after the Metropolitan Railway. | London Transport Museum: Metropolitan line | 2 passed |
| 4 | London had about 1.7 million people when Queen Victoria was crowned in 1837, and the main-line railways of the 1840s and 1850s brought in even more. | London Transport Museum: Public transport in Victorian London: Underground | 1 passed |
| 5 | Crossing London could take an hour and a half: five miles from Paddington to Bank by horse-drawn omnibus. | London Transport Museum: Public transport in Victorian London: Underground | 1 passed |
| 6 | In 1846 a Royal Commission ruled that new railways should be kept out of the City and the West End. | London Transport Museum: Public transport in Victorian London: Underground | 1 passed |
| 7 | Charles Pearson, Solicitor to the City of London, championed an underground railway to link the main-line stations. | London Transport Museum: Public transport in Victorian London: Underground | 1 passed |
| 8 | Britannica says Pearson proposed it as part of a plan to improve the city, soon after the Thames Tunnel opened in 1843. | Britannica: London Underground (with Britannica’s subway article, on the same page) | 1 passed |
| 9 | Pearson’s plans and a rival group’s merged, and the Metropolitan Railway Company was formed in August 1854. | London Transport Museum: Public transport in Victorian London: Underground | 1 passed |
| 10 | Objectors feared the tunnels would collapse under the traffic and that passengers would choke on the fumes from the engines. | London Transport Museum: Public transport in Victorian London: Underground | 2 passed |
| 11 | The £1 million needed took five years to raise. | London Transport Museum: Public transport in Victorian London: Underground | 1 passed |
| 12 | Work began in 1860. | London Transport Museum: The world’s first underground | 1 passed |
| 13 | It was built by ‘cut and cover’: a trench about ten metres wide and six metres deep was dug along the road, lined with brick walls and roofed with a brick arch, and the road was rebuilt on top. | London Transport Museum: Public transport in Victorian London: Underground | 2 passed |
| 14 | Building it took nearly two years and caused huge disruption; one complaint said a great street had been ‘turned into a builder’s yard’. | London Transport Museum: Metropolitan line | 2 passed |
| 15 | The London Transport Museum’s line history gives the first line as 5.6km long. | London Transport Museum: Metropolitan line | 1 passed |
| 16 | The museum’s story of Victorian transport says it ran for three miles under the New Road. | London Transport Museum: Public transport in Victorian London: Underground | 1 passed |
| 17 | Britannica says Parliament authorised 3.75 miles (6km) of underground railway. | Britannica: London Underground (with Britannica’s subway article, on the same page) | 1 passed |
| 18 | The London Transport Museum says it opened with seven stations, from Paddington (Bishop’s Road) to Farringdon Street. | London Transport Museum: Metropolitan line | 1 passed |
| 19 | Transport for London says it opened between Paddington and Farringdon, serving six stations in between. | Transport for London: London’s transport, a history: London Underground | 1 passed |
| 20 | The first trains were pulled by steam locomotives burning coke and, later, coal. | Britannica: London Underground (with Britannica’s subway article, on the same page) | 1 passed |
| 21 | Engines were fitted with water tanks to condense their steam, but the smoke and fumes stayed a problem. | London Transport Museum: Public transport in Victorian London: Underground | 2 passed |
| 22 | Despite the fumes it was a success, carrying 9.5 million passengers in its first year. | Britannica: London Underground (with Britannica’s subway article, on the same page) | 1 passed |
| 23 | Metropolitan locomotive No. 23, of 1866, is the only steam engine from the 1860s to survive, and is on show at the London Transport Museum. | London Transport Museum: The world’s first underground | 1 passed |
| 24 | A second underground line, the District, opened five years later, in 1868. | London Transport Museum: The world’s first underground | 1 passed |
| 25 | The two companies fell out, and the Inner Circle linking the main-line stations was not finished until 1884. | London Transport Museum: The world’s first underground | 1 passed |
| 26 | The District first opened on Christmas Eve 1868, between South Kensington and Westminster. | Transport for London: London’s transport, a history: London Underground | 1 passed |
| 27 | The name ‘Metro-land’ was coined in 1915 to sell homes along the Metropolitan’s lines. | London Transport Museum: Metropolitan line | 1 passed |
| 28 | Marc Isambard Brunel’s Thames Tunnel, the world’s first tunnel under a river, opened between Wapping and Rotherhithe in 1843. | London Transport Museum: Public transport in Victorian London: Underground | 1 passed |
| 29 | James Greathead’s tunnelling shield was pushed forward through the clay, and the tunnel behind it was lined with cast-iron rings to make a ‘tube’. | London Transport Museum: Public transport in Victorian London: Underground | 1 passed |
| 30 | London’s Underground is often called the Tube because of the shape of its tunnels. | Britannica: London Underground (with Britannica’s subway article, on the same page) | 1 passed |
| 31 | The City & South London Railway, the world’s first deep-level electric railway, opened in November 1890, between King William Street in the City and Stockwell. | London Transport Museum: Public transport in Victorian London: Underground | 2 passed |
| 32 | Every journey on it cost the same fare of twopence. | Britannica: London Underground (with Britannica’s subway article, on the same page) | 1 passed |
| 33 | Its carriages had tiny windows near the roof, as it was thought passengers would not need to see out; they were nicknamed ‘padded cells’. | London Transport Museum: Public transport in Victorian London: Underground | 2 passed |
| 34 | It was so busy at rush hour that Punch magazine called it the ‘sardine box railway’. | London Transport Museum: Public transport in Victorian London: Underground | 1 passed |
| 35 | The two-station Waterloo & City opened in 1898; it was nicknamed ‘the Drain’. | Transport for London: London’s transport, a history: London Underground | 1 passed |
| 36 | The Central London Railway opened on 30 July 1900, from Bank to Shepherd’s Bush, for a flat fare of two old pence: the ‘Tuppenny Tube’. | Transport for London: London’s transport, a history: London Underground | 2 passed |
| 37 | From 1900 the American railway magnate Charles Tyson Yerkes built more tube lines and electrified the older ones. | Britannica: London Underground (with Britannica’s subway article, on the same page) | 1 passed |
| 38 | The Bakerloo opened on 10 March 1906, and more than 36,000 people used it that day. Its name, a nickname for the Baker Street and Waterloo Railway, was made official in July 1906. | Transport for London: London’s transport, a history: London Underground | 2 passed |
| 39 | The Piccadilly opened on 15 December 1906, from Finsbury Park to Hammersmith. | Transport for London: London’s transport, a history: London Underground | 1 passed |
| 40 | In 1908 the separate companies began promoting the system together under the name ‘Underground’. | London Transport Museum: A very short history of the Underground | 1 passed |
| 41 | In 1933 all of London’s buses, trams, trolleybuses and Underground railways came under public ownership. | London Transport Museum: A very short history of the Underground | 1 passed |
| 42 | The Northern line was formed out of two railways, the City and South London and the Hampstead line, and got its name in 1933. | Transport for London: London’s transport, a history: London Underground | 2 passed |
| 43 | The Victoria line opened in stages from 1968 to 1971, the first new line across central London for more than 60 years. | Transport for London: London’s transport, a history: London Underground | 2 passed |
| 44 | It was the world’s first automatic passenger railway: at the press of a button, the train closed its doors and drove itself to the next station. | Transport for London: London’s transport, a history: London Underground | 1 passed |
| 45 | The Jubilee line opened on 1 May 1979, and was extended to Stratford through the Docklands in 1999. | Transport for London: London’s transport, a history: London Underground | 2 passed |
| 46 | The Tube reached Heathrow Airport in 1977. | London Transport Museum: A very short history of the Underground | 1 passed |
| 47 | Heathrow Terminal 5 station opened in 2008. | Transport for London: London’s transport, a history: London Underground | 1 passed |
| 48 | In 2021 the Northern line was extended to Battersea Power Station and Nine Elms, the first big Tube extension of the 21st century. | Transport for London: London’s transport, a history: London Underground | 2 passed |
| 49 | New Metropolitan line trains of 2012 were the first on the Underground with air conditioning and walk-through carriages. | Transport for London: London’s transport, a history: London Underground | 1 passed |
| 50 | All-night weekend services began on some lines in 2016. | London Transport Museum: A very short history of the Underground | 1 passed |
| 51 | Since December 2009 the Circle line has not been a closed circle: it runs from Hammersmith to Edgware Road via Aldgate. | Transport for London: London’s transport, a history: London Underground | 1 passed |
| 52 | The name ‘Circle line’ first appeared on a poster in 1936, and the line got its own line on the Tube map in 1949. | Transport for London: London’s transport, a history: London Underground | 2 passed |
| 53 | Amersham is the highest station above sea level, at 147m. | London Transport Museum: Metropolitan line | 1 passed |
| 54 | The longest gap between neighbouring stations is the 6.2km from Chesham to Chalfont & Latimer. | London Transport Museum: Metropolitan line | 1 passed |
| 55 | Steam passenger trains ran on the Metropolitan beyond Rickmansworth until 1961. | London Transport Museum: Metropolitan line | 1 passed |
| 56 | The Hammersmith and City Railway opened on 13 June 1864, as a branch feeding the Metropolitan; it became a line in its own right in 1988. | Transport for London: London’s transport, a history: London Underground | 2 passed |
| 57 | Transport for London says the network has grown to 272 stations and 11 lines. | Transport for London: London’s transport, a history: London Underground | 1 passed |
| 58 | Generations of Londoners have called it ‘the Tube’. | Transport for London: London’s transport, a history: London Underground | 1 passed |
| 59 | In 1919 the Metropolitan Railway began building houses itself, through Metropolitan Railway Country Estates Limited. | Transport for London: London’s transport, a history: London Underground | 1 passed |
| 60 | Metro-land was the subject of a 1973 BBC TV documentary presented by the Poet Laureate, Sir John Betjeman. | Transport for London: London’s transport, a history: London Underground | 1 passed |
| 61 | White City took its name when the Central line was extended to the 1908 Franco-British Exhibition, which drew 8 million visitors. | Transport for London: London’s transport, a history: London Underground | 2 passed |
| 62 | Rumour has it the Bakerloo was built after businessmen complained they could not get to Lord’s Cricket Ground quickly enough. | Transport for London: London’s transport, a history: London Underground | 1 passed |
| 63 | The Waterloo & City became part of London Underground in 1994, making it, at the time, the Underground’s 12th line. | Transport for London: London’s transport, a history: London Underground | 1 passed |
| 64 | The Underground now has 11 lines covering 402km and serving 272 stations. | London Transport Museum: A very short history of the Underground | 1 passed |
| 65 | It handles up to five million passenger journeys a day. | London Transport Museum: A very short history of the Underground | 1 passed |
| 66 | At the busiest times more than 543 trains are running, and the busiest line runs 40 trains an hour. | London Transport Museum: A very short history of the Underground | 1 passed |
| 67 | Britannica says it had about 400km of track and some 270 stations at the start of the 21st century, carrying more than a billion passengers a year. | Britannica: London Underground (with Britannica’s subway article, on the same page) | 1 passed |
| 68 | In 2016/17, 1.37 billion journeys were made, more than two and a half times the post-war low of 498 million in 1982. | Transport for London: London’s transport, a history: London Underground | 2 passed |
| 69 | London Underground became part of Transport for London in 2003. | Transport for London: London’s transport, a history: London Underground | 1 passed |
| 70 | An automatic announcement warns passengers to ‘mind the gap’ between the train and the platform. | Britannica: London Underground (with Britannica’s subway article, on the same page) | 1 passed |
| 71 | The Underground’s 150th birthday in 2013 was marked with a steam locomotive and 19th-century carriages running through central London. | London Transport Museum: A very short history of the Underground | 2 passed |
| 72 | In 1933 the private companies were nationalised into one body, the London Passenger Transport Board. | Transport for London: London’s transport, a history: London Underground | 1 passed |
| 73 | The first maps showing the whole Underground were produced in 1908, as posters and folding pocket maps, with colour-coded lines over a simplified street map. | London Transport Museum: Transforming the Tube map: Harry Beck’s iconic design | 1 passed |
| 74 | Harry Beck, a draughtsman for the Underground, designed a new kind of map in his spare time in 1931. | London Transport Museum: Mapping London: the iconic Tube map | 1 passed |
| 75 | Beck had worked as a draughtsman for the Underground since 1924, and drew the map during a spell out of work in 1931. | London Transport Museum: Transforming the Tube map: Harry Beck’s iconic design | 2 passed |
| 76 | He used only horizontal, vertical and 45-degree lines, enlarged the crowded centre and squeezed the outer ends. | London Transport Museum: Transforming the Tube map: Harry Beck’s iconic design | 1 passed |
| 77 | The map gave up geographical accuracy so that passengers could understand the network more quickly. | London Transport Museum: Mapping London: the iconic Tube map | 1 passed |
| 78 | At first the Underground’s publicity department rejected it as too revolutionary. | London Transport Museum: Mapping London: the iconic Tube map | 1 passed |
| 79 | Beck made station names bigger and swapped round ‘blobs’ for the now-familiar ‘ticks’. | London Transport Museum: Mapping London: the iconic Tube map | 1 passed |
| 80 | The first pocket map was printed in January 1933, with a note asking users for their comments. | London Transport Museum: Transforming the Tube map: Harry Beck’s iconic design | 1 passed |
| 81 | Maps were usually printed 10,000 to 20,000 at a time, but the first print run of Beck’s map was 750,000. | London Transport Museum: Transforming the Tube map: Harry Beck’s iconic design | 1 passed |
| 82 | Frank Pick called it ‘very convenient and tidy’ and ‘a better map than any we have had so far’. | London Transport Museum: Transforming the Tube map: Harry Beck’s iconic design | 2 passed |
| 83 | It was an immediate success with passengers. | London Transport Museum: Mapping London: the iconic Tube map | 1 passed |
| 84 | In 1935 the Bakerloo and Central lines, red and orange and hard to tell apart under artificial light, were changed to brown and red. | London Transport Museum: Mapping London: the iconic Tube map | 2 passed |
| 85 | Beck thought his 1950 map was his finest; it was the first to show the Circle line separately. | London Transport Museum: Mapping London: the iconic Tube map | 2 passed |
| 86 | In 1960 Beck was replaced as the map’s designer without being told, and was deeply hurt. | London Transport Museum: Transforming the Tube map: Harry Beck’s iconic design | 1 passed |
| 87 | Harry Beck died in September 1974. | London Transport Museum: Transforming the Tube map: Harry Beck’s iconic design | 1 passed |
| 88 | Since 2001 every Underground map has carried a credit saying it is an evolution of Beck’s 1931 design. | London Transport Museum: Transforming the Tube map: Harry Beck’s iconic design | 1 passed |
| 89 | In 2006 the map was voted the second-favourite British design of the 20th century. | London Transport Museum: Transforming the Tube map: Harry Beck’s iconic design | 1 passed |
| 90 | Other cities’ railways, including New York, Sydney and St Petersburg, have borrowed Beck’s idea. | London Transport Museum: Mapping London: the iconic Tube map | 1 passed |
| 91 | Beck even drew a proposal for the Paris Métro, which was not used. | London Transport Museum: Mapping London: the iconic Tube map | 1 passed |
| 92 | The roundel first appeared on station platforms in 1908, as a solid red disc with a blue bar across it, used as a station name board. | London Transport Museum: The evolution of the roundel | 2 passed |
| 93 | It made the station’s name stand out from the advertisements around it. | London Transport Museum: The evolution of the roundel | 1 passed |
| 94 | In 1915 the Underground’s publicity manager, Frank Pick, asked the calligrapher Edward Johnston to design a typeface for the company. | London Transport Museum: The evolution of the roundel | 1 passed |
| 95 | Johnston sent Pick the first examples of his capital block letters in February 1916. | London Transport Museum: Edward Johnston, the man behind London’s lettering | 1 passed |
| 96 | By 1917 the roundel had been redrawn to suit the new lettering: the solid disc became a ring, and it was registered as a trademark. | London Transport Museum: The evolution of the roundel | 1 passed |
| 97 | Johnston called it the ‘bullseye’. | London Transport Museum: The evolution of the roundel | 1 passed |
| 98 | The Johnston typeface is a sans serif: its letters have no small strokes, or serifs, at their ends. | London Transport Museum: Edward Johnston, the man behind London’s lettering | 1 passed |
| 99 | Edward Johnston was born to Scottish parents in Uruguay, and his family moved to England when he was three. | London Transport Museum: Edward Johnston, the man behind London’s lettering | 2 passed |
| 100 | In 1906 he published the influential book Writing & Illuminating & Lettering. | London Transport Museum: Edward Johnston, the man behind London’s lettering | 1 passed |
| 101 | Pick’s aim was to raise fare income by making the Underground better publicised, its stations easier to spot and the system easier to use. | London Transport Museum: Edward Johnston, the man behind London’s lettering | 1 passed |
| 102 | From 1924 Pick asked the architect Charles Holden to design new stations, and Holden built the roundel into them, on masts outside and in stained-glass windows. | London Transport Museum: The evolution of the roundel | 2 passed |
| 103 | In 1979 Eiichi Kono, a young Japanese designer, revised Johnston’s letters and added bold and italic versions. | London Transport Museum: Edward Johnston, the man behind London’s lettering | 1 passed |
| 104 | Monotype’s update, Johnston100, has been rolled out by TfL since 2016. | London Transport Museum: Edward Johnston, the man behind London’s lettering | 1 passed |
| 105 | Transport for London, created on 3 July 2000, uses a family of roundels in different colours for its different services. | London Transport Museum: The evolution of the roundel | 2 passed |
| 106 | The roundel is now one of the most recognised and copied logos in the world. | London Transport Museum: The evolution of the roundel | 1 passed |
| 107 | The first ever air raid on London, on 31 May 1915, sent people into Underground stations for shelter. | London Transport Museum: Shelter in wartime | 1 passed |
| 108 | In the Blitz, from September 1940 to May 1941, deep Tube stations sheltered thousands of people every night. | London Transport Museum: Deep-level shelters | 1 passed |
| 109 | At first the authorities did not want people sheltering in the Underground, but the Blitz changed their minds. | London Transport Museum: Shelter in wartime | 2 passed |
| 110 | People slept on walkways, platforms and even tracks with the power switched off. | London Transport Museum: Shelter in wartime | 1 passed |
| 111 | A ‘Tube Refreshments Special’ train delivered food and drink to shelterers. | London Transport Museum: Shelter in wartime | 1 passed |
| 112 | London Transport built eight deep-level shelters, at Belsize Park, Camden Town, Chancery Lane, Goodge Street, Stockwell, Clapham North, Clapham Common and Clapham South, each for 8,000 people. | London Transport Museum: Deep-level shelters | 1 passed |
| 113 | Ten were planned; the two at Oval and St Paul’s were abandoned during building. | London Transport Museum: Deep-level shelters | 2 passed |
| 114 | Their tunnels were dug by hand, 30 metres down and just over 400 metres long. | London Transport Museum: Deep-level shelters | 1 passed |
| 115 | Some opened to the public in July 1944, when V1 flying bombs and V2 rockets were hitting London. | London Transport Museum: Deep-level shelters | 2 passed |
| 116 | Each had eight canteens serving sausage rolls, meat pies and cakes, a treat in a time of strict rationing. | London Transport Museum: Deep-level shelters | 1 passed |
| 117 | Shelterers slept on hard three-tier bunk beds and brought their own bedding. | London Transport Museum: Deep-level shelters | 2 passed |
| 118 | After the war some shelters housed some of the first people from Jamaica to arrive on the Empire Windrush, in 1948. | London Transport Museum: Deep-level shelters | 1 passed |
| 119 | Britannica says that in the wars the unused Aldwych tunnels stored treasures from the British Museum. | Britannica: London Underground (with Britannica’s subway article, on the same page) | 1 passed |
| 120 | The Aldwych branch of the Piccadilly line closed in 1994, with too few passengers and high costs. | Transport for London: London’s transport, a history: London Underground | 1 passed |