Inchiquin Castle is located on the north side of Lake Inchiquin (in the parish of Kilnaboy). It was possibly begun by Teige-an-Chomhaid O'Brien (d. 1466). In 1542, it belonged to Turlough, son of Murrough, first Baron of Inchiquin. Murrough O'Brien, the fourth Baron, was in possession in 1580. His descendants, the Marquesses of Thomond, derived their title of Earl of Inchiquin from this estate. During the Nine Years' War, Hugh Roe O'Donnell raided Clare and Inchiquin Castle was attacked by one of his lieutenants, Maguire of Fermanagh. During the Confederate Wars Christopher O'Brien, Murrough the Burner's brother, lived here. Murrough's son, Colonel John O'Brien, abandoned Inchiquin towards the end of the 17th century. By then it had deteriorated into a ruin. Today the castle remains a ruin surrounded by pastures. Part of the older castle tower is still extant as is a good portion of the later 17th-century banquet hall.