Big Ben is an iconic clock tower located in the heart of London, England. Built in 1859, the tower stands at a height of 316 feet and is the largest four-faced clock in the world. The clock's four faces are each 23 feet in diameter
From Wikipedia
Big Ben is the nickname for the Great Bell of the Great Clock of Westminster, and, by extension, for the clock tower which stands at the north end of the Palace of Westminster in London, England. Originally named the Clock Tower, the structure was renamed the Elizabeth Tower in 2012 to mark the Diamond Jubilee of Queen Elizabeth II. The clock is a striking clock with five bells.