Castlemartyr Castle lies in the town of Castlemartyr, in County Cork in Ireland.
After James, Earl of Ormond, governor of Imokilly, appointed a local seneschal for the area in 1420, Castlemartyr was built to serve as the seneschals' seat.
It was captured by Sir Henry Sidney in 1569, after the garrison abandoned it during the night following an exchange of cannonfire. It was later granted to Sir Walter Raleigh only to be recovered by the seneschal of the time, John FitzEdmund FitzGerald, only to be attacked again in 1579 by the Earl of Ormond, who hanged John's mother outside the walls. John finally submitted in 1583 and died in Dublin Castle in 1589.
During the wars of the 1640s Castlemartyr Castle was captured by Lord Inchiquin but then fell to a raiding party led by Sir Percy Smith, who burnt the castle to prevent it being used as a base for the Irish Confederate forces. It was repaired in the 1650s and inhabited by Lord Broghill, later Earl of Orrery, until his death in 1679. During the civil war it was captured by the Irish, only to be retaken by the Williamites in 1690. This left the castle badly damaged and it was subsequently abandoned and fell into disrepair.
During the 18th century the castle became a farm- and coachyard for a newly build manor to the west. In 2007 this manor opened as the Castlemartyr Resort, a luxury spa and 5-star hotel.
Castlemartyr Castle was a roughly rectangular castle with a 5-storey square keep at its eastern corner. The large chimney stacks were part of a 17th century range built against the inner wall. There is a smaller tower at the northern corner of the enclosure.
A nice castle ruin. It can be visited as a guest of the resort, although the interior of the keep itself can not be visited.