Big Ben, London. Famous around the world for keeping impeccable time, the Big Ben Clock Tower was fully operational on September 7th, 1859. The Big Ben Clock is used to ring in the London New Year and is a rallying point for the New Year's celebration of the entire country. The name Big Ben actually refers to the bell housed within the tower. The bell itself weighs almost 14 tons, and the four clock faces of the Big Ben in London are each 23 feet in diameter.