How to win the pub quiz, or set the unanswerable one. When did the last steam train run on the London Underground?
Astonishingly, the answer is June 1967 - they were used for transporting night-time maintenance crews. No wonder the native mice are soot-coloured.
And with the new Wembley Stadium apparently in trouble, it seems the site has a problematic history. Sir Edward Watkins, the chairman of the Metropolitan line, set out to build a tower higher than the Eiffel that was supposed to attract customers. It was not a success, and was never completed.
The Northern Line, as it is today, started out badly, as it was to continue. The carriages were called "padded cells", because there were no windows - the theory being there was nothing to look at.
From: Underground London: Travels Beneath the City Streets Stephen Smith, Little, Brown, 2004.