Construction began on January 26 1887, with not a moment to spare. With barely two years left to build the tower in time for opening of the Exposition, Eiffel would have to build the tower more quickly than any similar structure had been built before.

• Every seven years, the Eiffel Tower receives a fresh coat of more than 50 tons of brown paint. Why brown? Because, tower officials say, it is the colour that clashed least with the blue sky over Paris, and the green landscape of the Champ de Mars below.

• The positions of the Eiffel Tower’s four "feet" correspond to the "cardinal" points of a compass: they point exactly north, south, west, and east.