The castle consists of a shell keep with an enclosing curtain wall, a corner tower and a gate tower. The shell keep is the earliest structure, dating from the 12th century and is very unusual for Ireland. The first constable was Thomas Fitz Anthony who was appointed by King John in 1215. The last constable was Lt. Col. Laurence Byrne (1689-1690). Inside the curtain wall is a two storey military barracks, which dates from the first half of the 18th century. The barracks was restored in the year 2000 and includes exhibition and visitor facilities. Access to the castle is restricted due to ongoing conservation works.
Restricted access to castle for visitors with disablities. Exhibition centre is fully accessible to visitors with disabilities.