The title Big Ben, which the tower is commonly known by actually refers to the bells housed within it weighing 13.5 tons .
The new work on Westminster Underground Station had caused the 8,600 ton tower to start to list and crack away. It was shored up by having concrete injected under the foundations.
The pendulum for the clock is 4.4m in size. The roman numerals are 61cm each in length and each of the minute squares is 30.5cm. There are 312 panes of glass on each clock face.
