London: a sold bridge, a great fire and a bell called Big Ben

London has been burned, restored and reinvented for two thousand years, and many of its most famous landmarks are not quite what they seem. This quiz invites you to test what you know about the city in 20 questions with pictures.

What lifted the great road spans of the bridge by the Tower when it opened in 1894, and what became of the granite bridge that stood upstream until 1968? Who built the pale keep at the heart of the Tower, and which monarch, according to legend, would not let its ravens go? How was the Great Fire of 1666 finally stopped, and what does the height of the Monument actually measure?

What holds up the lantern on top of the dome of St Paul's? What exactly is Big Ben, and how did an October night in 1834 destroy the old Palace of Westminster? Which creature inspired the first tunnel dug under the Thames, what came of the summer when Parliament could not bear the river's smell, and what did a doctor's map of Soho reveal in 1854?

How were the first underground trains of 1863 pulled, and how did the government react when Londoners took refuge in the Tube in 1940? Who was the warrior queen in the chariot by Westminster Bridge, whose funeral appears in the Bayeux Tapestry, what was the real Dick Whittington, where does the 'Bow' of Bow Bells come from, who designed the Crystal Palace and what happened to Shakespeare's Globe in 1613?

The pictures are old photographs and colour photochroms, engravings, cartoons, maps, paintings and a lithograph, all in the public domain.