Which royal residence gets its name from a title held by William IV before he became king of the UK?

Clarence House is a British royal residence on The Mall in the City of Westminster, London. It was built in 1825-1827, adjacent to the royal palace of St James's for the royal, Duke of Clarence, the future king, William IV.

Over the years, it has undergone extensive remodelling and reconstruction, most notably after being damaged during the Second World War, and little remains of the original structure as designed by John Nash. It is Grade I listed (building of exceptional interest) on the National Heritage List for England.

Clarence House is the official residence of Charles, Prince of Wales, and his wife Camilla, Duchess of Cornwall. Since 2003, the term 'Clarence House' has been used as a metonym for the private office of the Prince of Wales.