St Paul's Cathedral, London, is an Anglican cathedral, the seat of the Bishop of London and the mother church of the Diocese of London. It sits on Ludgate Hill at the highest point of the City of London and is a Grade I listed building. Its dedication to Paul the Apostle dates back to the original church on this site, founded in AD 604. The present cathedral, dating from the late 17th century, was designed in the English Baroque style by Sir Christopher Wren. Its construction, completed in Wren's lifetime, was part of a major rebuilding programme in the City after the Great Fire of London. [page needed] The cathedral building largely destroyed in the Great Fire, now often referred to as Old St Paul's Cathedral, was a central focus for medieval and early modern London, including Paul's walk and St. Paul's Churchyard being the site of St. Paul's Cross.