Kenmure Castle is a country house located in The Glenkens, 1 mile (1.6 km) south of the town of New Galloway in Dumfries and Galloway, south-west Scotland. The site was occupied from the Middle Ages, and the house incorporates part of a 17th-century castle. This was remodelled in the 19th century, but the house has been derelict since the mid-20th century. It was the seat of the Gordon family of Lochinvar, later raised to the peerage as Viscounts of Kenmure. The ruin is a category B listed building and a scheduled monument.
The present castle stands on a partly natural mound, which may have been modified for defence in the early Middle Ages. The Lords of Galloway, rulers of a semi-independent kingdom in south-west Scotland until the 13th century, may have had a fortress here. Kenmure has been suggested as a possible birthplace in 1249 of John Balliol, later King of Scotland, whose mother Dervorguilla was daughter of Alan, the last independent Lord of Galloway. It later belonged to the Douglas and Maxwell families.
Kenmure became a property of the Gordon family from 1297, when they arrived from Berwickshire. The Gordons built a castle on an island in Lochinvar, some 6 miles (9.7 km) to the north. An early castle which stood here was destroyed or damaged by opponents of Mary, Queen of Scots, who marched through the south-west after they defeated her supporters at the Battle of Langside (1568).
Sir Robert Gordon of Lochinvar was created a baronet in 1626, and in 1633 his son Sir John Gordon was created Viscount of Kenmure by Charles I in 1633. The core of the present building is the castle which was largely erected in the 17th century, though possibly including earlier building work. The castle was laid out on the west and south sides of a courtyard, with the north and east sides formed by a high wall. The entrance gate in the north wall was flanked by towers at the two northern corners. The 6th Viscount took part in the Jacobite Rising of 1715 and was subsequently beheaded and his estates forfeit. By 1790 Kenmure Castle was described as a ruin.