Big Ben Facts
Each dial is seven metres in diameter
The minute hands are 4.2 metres long and weigh about 100kg (including counterweights)
The numbers are approximately 60cm long
There are 312 pieces of glass in each clock dial
A special light above the clock faces is illuminated when parliament is in session
Big Ben's timekeeping is strictly regulated by a stack of coins placed on the huge pendulum.
Big Ben has rarely stopped. Even after a bomb destroyed the Commons chamber during the Second World War, the clock tower survived and Big Ben continued to strike the hours.
The chimes of Big Ben were first broadcast by the BBC on 31 December 1923, a tradition that continues to this day.
The latin words under the clockface read DOMINE SALVAM FAC REGINAM NOSTRAM VICTORIAM PRIMAM, which means O Lord, keep safe our Queen Victoria the First
In June 2012 the House of Commons announced that the clock tower was to be renamed the Elizabeth Tower in honour of Queen Elizabeth II's Diamond Jubilee.