Big Ben Fast Facts

Fireworks light up the London skyline and Big Ben just after midnight on January 1, 2012.

(CNN)Here's some background information about Big Ben, the clock and bell in Elizabeth Tower, formerly St. Stephen's Tower, at the Houses of Parliament in London. It is one of the most famous landmarks in England.

The name "Big Ben" originally referred to just the bell of the clock, but has also come to indicate the clock, the tower and the bell.
Big Ben chimes on the hour and has quarter bells that chime every fifteen minutes.
    September 28, 1843 -
    Construction on the clock tower begins. The foundation stone is laid nearly ten feet (3 meters) deep.
    February 1852 - Clockmaker Edward John Dent wins the competition to design the clock, beating Benjamin Lewis Vuillamy.
    1853 - Dent passes away, but his stepson, Frederick Dent, finishes building the Great Clock in 1854.
    August 1856 - The bell is cast in northern England and transported to London. It develops a crack measuring almost 4 feet (1.2 meters) in October 1857. Rather than recast the first bell, a second bell is cast by George Mears in 1858.
    April 10, 1858 - The second bell, 2.5 tons lighter than the original, is cast or molded.
    1859 - Construction on the tower is complete, five years overdue.
    May 31, 1859 - The clock begins keeping time.
    July 11, 1859 - Big Ben chimes for the first time.
    September 1859 - Big Ben cracks two months after its first chime and remains silent for the next four years. The fourth quarter bell rings out the hour. In 1863, the bell is turned so an undamaged portion is now struck with a smaller hammer. The crack is still there today.
    1923 - Big Ben's chimes are broadcast to the United Kingdom for the first time by BBC Radio, on New Year's Eve.
    1939-April 1945 - The clock dials are unlit due to wartime blackout regulations.
    August 1976 - Nine months of repairs begin.
    2007 - Big Ben is silent for seven weeks for maintenance.
    2009 - Special events all year mark Big Ben's 150th anniversary.
    2011 - It becomes apparent that Big Ben has started to lean to one side. It is estimated that there is a change of less than one millimeter per year.
    September 12, 2012 - St. Stephen's Tower is renamed Elizabeth Tower in honor of Queen Elizabeth II's Diamond Jubilee, or 60th anniversary on the throne.
    October 2015 - According to a parliamentary report seen by both the Mail on Sunday and Sunday Times newspapers: British lawmakers believe Big Ben may stop working altogether if it is not refurbished. The report claims that a structural overhaul is necessary at a cost of about $45 million (£29.9 million) -- in work that would see it shut down for four months.
    Bell Characteristics:
    8'-8'' in diameter
    7'-2" high
    Weighs 13 tons
    Elizabeth Tower, where the bell resides, stands 316 feet (96 meters) tall.
    The bell can be heard as far as 9 miles away.
    The clock that Ben rings for weighs about 5 1/2 tons. Each of the four clock faces is 23 ft. in diameter, the hour hands are 9 ft long, the minute hands are 14 ft. long and the numbers are 2 ft high.