London is a complex web of railway lines and train stations; one that is only understandable thanks to the power of the Tube Map. But how did it get to be the way it is? The history is rather more complex than you might think, thanks to the network's origins as a collection of independent companies during the Victorian era.
Brilliantly, to explain the confusion and to help you nerd-out next time you travel through Mansion House on the Circle Line, Geoff Marshall of the Londonist has put together this 3D animation showing what happened chronologically:
(If you like this you'll probably also love Geoff's Secrets of the Underground series too.)
The Tube Map has long fascinated Londoners. So much so that many unofficial versions have been produced, including one that shows what each station tastes like and this version for colourblind travellers. [Londonist]