Greenan Castle, situated on a rocky crag 2.5 miles southwest of Ayr, is a dramatic 16th-century ruined tower house overlooking Ayr Bay and the Firth of Clyde. The castle occupies an ancient defensive position, built upon what was originally a promontory fort converted to a motte-and-bailey fortification in the 12th century. In the 15th century, the Lords of the Isles constructed the stone tower, which later passed to the Kennedy family, notable landowners and patrons of the region. An inscribed lintel marks the ownership of John Kennedy and his wife Florence in 1603. The castle gained literary fame when Sir Walter Scott drew inspiration from a tragic 1602 incident—the murder of Sir Thomas Kennedy and his servant—to write his play 'An Ayrshire Tragedy'. Now a scheduled monument under Historic Environment Scotland's protection, Greenan remains one of Scotland's most photographed ruins.