Fodor's Expert Review Craigmillar Castle

This handsome medieval ruin, just 3 miles south of the city center, is the archetypal Scottish fortress: forbidding, powerful, and laden with atmosphere. It is best known for its association with Mary, Queen of Scots: during a stay here in 1563, her courtiers hatched the successful plot to murder her troublesome husband, Henry Stuart (possibly with Mary's approval). Today Craigmillar is one of the most impressive ruined castles in Scotland. Stroll its beautiful courtyard, enter the well-preserved great hall, or climb the 15th-century tower for a superb view across the city. Look out for the unusually ornate defensive arrow slits, shaped like inverted keyholes.