Dedicated to St. Paul the Apostle, this Anglican Church is the seat of the Bishop, as well as the Mother Church of the Diocese of London. It is located on the highest point in the city - Ludgate Hill. The original church on this site was founded in 604 AD. This and two succeeding structures were destroyed by fires over the centuries. The present church dates from the late 17th century, following the Great Fire of 1666 that destroyed most of London. Sir Christopher Wren was commissioned to design the new St. Paul's (along with fifty other churches throughout the city). Reaching a height of 365 feet, it was the tallest building in the city between 1710 and 1962 and its impressive dome is the highest in the world. Many of the United Kingdom's important events occurred in St. Paul's, including the funerals of Lord Nelson, the Duke of Wellington, Sir Winston Churchill, and Margaret Thatcher, along with the wedding of Prince Charles and Lady Diana Spencer. During "the Blitz" of World War II, the cathedral was struck by bombs in 1940 and 1941, causing damage that included a crack along the circumference of the dome when it reportedly "jumped" a couple of centimeters after an explosion. The cathedral's organ, built in 1694, is the fourth largest in Great Britain with 7,266 pipes, 5 manuals, 189 ranks of pipes, and 108 stops. Perhaps the most distinctive feature of St. Paul's is the Dean's spiral staircase, designed by Wren in 1705. The treads are imbedded only a short distance into the supporting walls, with each succeeding tread resting on the one below. Wren was very proud of this design, although it did create some controversy amongst the architects of the time.