The British monarch's official Northern Ireland residence is this rambling, late-Georgian mansion, which was built in 1797 for Wills Hill, the first Marquess of Downshire, and extensively remodelled in the 1830s and '40s. Hour-long guided tours take in the throne room, state drawing room and dining rooms, and the Lady Grey Room where, in 2003, Tony Blair and George W Bush held talks on Iraq. Highlights of the lovely gardens include the lime-tree walk and the restored, 18th-century walled garden.
The car park is accessed from the A1, just south of the turn-off for the village (follow signs). Last admission is one hour before closing.