1963
The Underground, more commonly called the Tube.
In London Underground (tube) stations.
It is an underground rail network underneath London.
London Underground is known by Londoners as 'the tube'.
The London underground system is usually referred to as 'the tube'.
If you are traveling on the tube, you are likely visiting London, where the tube is a common nickname for the London Underground, the city's underground subway system.
The Central line is the current oldest tube stock in the whole of the London Underground.
'The Tube'
It's usually called either the Underground or the Tube.
The London Underground, usually referred to as just 'the underground' or 'the tube'.
By underground (tube).
Use the tube (underground) from any terminal.