Crevenish Castle lies on the east bank of Lough Erne, west of the village of Kesh, in County Fermanagh, in Northern Ireland.
Crevenish Castle was built about 1618 by Sir Thomas Blennerhassett, from Norfolk, whose brother built Castle Caldwell and was originally known as Castlehassett or Castle Hassett. Sir Thomas was succeeded by his eldest son, Sir Leonard Blennerhassett. The castle moved to local Maguire hands when his widow, Deborah, married Rory Maguire, leader of the Irish Rebellion of 1641 in Fermanagh. When Rory died in 1648, the castle returned to the Blennerhassett family. In 1697, however, the castle was already described as being ruinous.
At present Crevenish Castle is private property and situated on the grounds of a caravan park and thus can not freely be visited. A nice ruin with nice views over the lough.