Big Ben in London mysteriously stopped ticking for 90 minutes today. Here is some history on the landmark clock:

Big Ben, which is operated by the Palace of Westminster, survived attacks by German Luftwaffe bombers during World War II, continuing to mark the time to within 1 1/2 seconds of Greenwich Mean Time.

However, the clock has experienced occasional problems.

In 1962, snow caused the clock to ring in the New Year 10 minutes late. In 1976, the clock stopped when a piece of its machinery broke. Big Ben also stopped on April 30, 1997, and once more three weeks later.

Big Ben is actually the clock's 13-ton bell, which was named after Sir Benjamin Hall, the British commissioner of works at the time the clock was built.

The official name for the Gothic tower holding Big Ben is St. Stephen's Tower. Standing 315 feet tall, it was completed in 1858 after an 1834 fire destroyed most of the Palace of Westminster.