Clarence House is situated in the City of Westminster, which is a borough of London, England. It is located on The Mall, near St. James's Palace and Buckingham Palace. Clarence House has served as the official residence of several members of the British royal family, including Prince Charles, the Prince of Wales, and his wife, Camilla, the Duchess of Cornwall. Please note that while Clarence House is located within the City of Westminster, it is not publicly accessible as a tourist attraction like Buckingham Palace.