Big Ben, London, England

1. Big Ben is the biggest four-faced, chiming clock in the world.

2. The real name of the tower, housing the clock, is 'Clock Tower'. Big Ben is the nickname of the main bell, formally known as the Great Bell, housed within the tower. However, the nickname is more popular than the official one.

3. Big Ben was built to replace the Old Palace of Westminster, after it was destroyed by fire in October 1834.

4. The clock became operational on 7th September 1859.

5. The Tower leans slightly towards northwest, by 8.66 inches.

6. The bell of 'Big Ben' weighs 14.5 tonnes. It is the huge size of the bell that inspired Benjamin Hall to give it the name of Big Ben.

7. The bell of Clock Tower did not stop working even during World War 2.