Every year,millions of tourists come to London to see and listen to Big Ben.But,what exactly is Big Ben?Most people think that Big Ben is the tall clock tower that stands above the Houses of Parliament.Well no!Big Ben is not the clock tower.It is one of the four huge bells inside the tower.Its name comes from the bell's commissioner of works,Sir Benjamin Hall,or Ben.The tower is 98 metres high.The bell inside the tower is 14 tons.The clock on the tower is also huge.Each of the four clock faces is 7 metres wide.The hour hands are about 3 metres long and the minute hands are about 4 metres long.Perhaps one day you can go to London and see this amazing tourist attraction.