Big Ben is the name commonly used for the bell, clock, and clock tower of the Houses of Parliament in the Palace of Westminster in London. The tower, officially named the Elizabeth Tower, is 316 feet (96 meters) tall. The tower was known as the Clock Tower until 2012, when it was renamed to honor the Diamond Jubilee (60th anniversary as queen) of Elizabeth II.
The clock weighs about 51/2 tons (5 metric tons). Each of the four clock faces is 23 feet (7 meters) in diameter. Each hour hand is 9 feet (2.7 meters) long, and each minute hand is 13.8 feet (4.2 meters) long. The numbers are 2 feet (0.6 meter) high. The bell in the tower can be heard at a distance of 9 miles (14 kilometers).
The tower was completed in 1858, after an 1834 fire destroyed most of the original Palace of Westminster. The name Big Ben at first referred only to the bell. Some historians believe the bell was named after Sir Benjamin Hall, commissioner of works when the tower was built.
