The Palace of Westminster was destroyed by fire in 1834. In 1844, it was decided the new buildings for the Houses of Parliament should include a tower and a clock.
A massive bell was required and the first attempt (made by John Warner & Sons at Stockton-on-Tees) cracked irreparably. The metal was melted down and the bell recast in Whitechapel in 1858. Big Ben first rang across Westminster on 31 May 1859. A short time later, in September 1859, Big Ben cracked. A lighter hammer was fitted and the bell rotated to present an undamaged section to the hammer. This is the bell as we hear it today.