Craignethan Castle is a ruined castle in South Lanarkshire, Scotland. It is located above the River Nethan, a tributary of the River Clyde, at. The castle is two miles west of the village of Crossford, and 4.5 miles north-west of Lanark. Built in the first half of the 16th century, Craignethan is recognised as an excellent early example of a sophisticated artillery fortification, although its defences were never fully tested.HistoryThe barony of Draffane, in which Craignethan was located, was a property of the Black Douglases until their forfeiture in 1455. The land was granted to the Hamilton family, and in 1530 was given by James Hamilton, 1st Earl of Arran to his illegitimate son James Hamilton of Finnart.James Hamilton of Finnart had travelled in Europe, and had become an accomplished architect and military engineer. Appointed Kings Master of Works, he was responsible for the defences at Blackness Castle, as well as the renaissance facades of Linlithgow Palace. At Craignethan, he set out to build a "showcase" to display his talents in both domestic and military architecture.Despite his earlier Royal favour, Hamilton was executed for treason in 1540, and his properties were forfeit to the crown. The Hamilton family, in the person of the 2nd Earl of Arran, regained Craignethan Castle two years later. The second earl added a large outer courtyard to the west of the castle. Arran, who became Duc de Châtellerault following Mary, Queen of Scots' marriage to the French Dauphin, served as regent in her infancy. However, he later opposed Mary's second marriage to Lord Darnley, and was forced to surrender his castles at Craignethan and Cadzow.