The World's Oldest Metro Systems - WorldAtlas
Another world first for London Underground: energy from braking trains | The Knowledge Exchange Blog
First stage of 'highly complex' London Underground resignalling goes live | Metro Report International | Railway Gazette International
World's first Underground | London Transport Museum
London Underground: Amazing images show houses being demolished for the Tube in 1863 | Daily Mail Online
First underground trains 1863 hi-res stock photography and images - Alamy
Tube - Transport for London
London Underground - Wikipedia
Where was the first metro rail in the world? - Quora
The world's first subway opened in London | History.info
Riding London's Unexpectedly Fantastic Elizabeth Line | The New Yorker
Subway | History, Transportation, Cities, & Facts | Britannica
London's first underground railway | The History of London
A history of the London Underground - CBBC Newsround
World's first Underground | London Transport Museum
The day the Queen drove a Tube train! Fascinating black and white images celebrate 150th anniversary of the London Underground | London underground tube, London underground train, Tube train
How the world's first metro system was built - Christian Wolmar - YouTube
Going underground: A metro-spective to celebrate 150 years of the tube | Underground, Vintage train, Subway
Why is the London Underground So Confusing? Part 2 - Fun London Tours
A short history of world metro systems – in pictures | Cities | The Guardian
A history of the London Underground - CBBC Newsround
First Day of the London Tube | History Today
New Tube for London - Wikipedia
A history of the London Underground - CBBC Newsround
