Love it or loathe it, the tube is an integral part of life in London - but there's more to the Underground than meets the eye.
Here are 5 interesting facts from its 154-year history.
Less than half of the network is actually underground
Given its name, you’d be forgiven for thinking that the London Underground runs predominantly under the city.
However, over half of the underground network is above ground.
Just 45% of underground stations are located underground - as highlighted by Transport for London’s new tube map, which shows the extent of the network located within tunnels.
The Central Line housed an aircraft factory
Throughout World War Two, many of the underground stations were used as air raid shelters, housing roughly 170,000 Londoners a night.
However, after the Plessey’s factory sustained damage from The Blitz, the company moved production of aircraft parts to the London Underground.
The factory was based between Newbury Park and Leytonstone and was an official secret until the 1980s.
Going the distance
According to Transport for London, trains on the tube travel the equivalent of 1,754 times around the world each year – equating to 90 journeys to the moon and back.
Their research also found that the distance the escalators in the underground travel each week is the same as going around the world twice.
There are 49 ‘ghost’ stations on the tube including Down Street, which was used as a bunker by Winston Churchill during World War Two.
The Bull & Bush, on the Northern Line by Hampstead, is the only station on the line which was started but never completed.
The lost property goldmine
Over the past 3 years, Transport for London made more than £2m selling lost property from the tube, buses and taxis.
TfL’s latest figures shows that the items recovered from April 2015 to March 2016 were worth £734,641.
A Freedom of Information request revealed that the total number of items found across the network in January 2017 alone was £29,232.
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