High on a promontory stand the impressive ruins of a Norman castle, built in 1269 by Robert of Ufford and once protected by a lake or marsh. Its massive walls, which are defended by circular bastions at each corner, enclose a large rectangular area. The main entrance is in the west wall. The mullion windows were inserted in the 16C by Nicolas Malby, Governor of Connaught, who probably occupied the castle in 1578.