Cloughoughter Castle

Clough Oughter Castle (in Irish Cloch Locha Uachtair, meaning 'stone castle of the Upper Lake') is located approximately half way between the towns of Cavan and Killeshandra in Co. Cavan.

Built in the 13th or early 14th century century by the O’Reilly family on a man-made island, or crannog in Irish, in Lough Oughter, one of the several beautiful lakes in the complex waterway system that is made up of promontories, peninsulas and islands of many shapes and sizes that lies between Killashandra to the west, Belturbet to the north, Cavan town to the east and the village of Crossdoney to the south. The castle is only accessible by boat, though when the lake’s water level is particularly low, some believe that the remains of a causeway can be seen. Within the lake are also to be found the islands of Eonish, Inch, and Trinity, on which is located the ruins of Trinity Abbey.

Annals compiled between 1632 and 1636, later combined to form the Annals of the Four Masters, document several historic activities as having taken place at Clough Oughter, the earliest of which dates to 1327, when "the Castle of Lough Oughter was taken by O’Rourke, but he delivered it up again for 20 cows." Over the course of the next three hundred years it would fall in and out of the hands of both Irish and English political and family interests. 

While there is speculation about the exact origins of the castle - some claiming that it was built in the 6th century, before the Round Tower at Drumlane was erected; or that it was put up by a long-forgotten Danish prince; while others say that it was built by the Sheridan family - the date of its destruction in the 17th century is well-known. 

History records that, during the Irish Rebellion of October 1641 to May 1642, the Rt. Rev. William Bedell, the fifth Provost of Trinity College and the Anglican Lord Bishop of Kilmore, Co. Cavan, a renowned scholar of Irish, and the translator of the Old Testament into that language, was imprisoned with his two sons and step-son for several weeks in the castle. The clergyman was deeply popular amongst all sections of society and on his death in February 1642 the O’Reilly chief of the rebel forces assembled at his graveside and accorded him an honourable farewell. 

The great Gaelic soldier, Owen Roe O’Neill, the leader of the national armies and the only military strategist who could deal effectively with Oliver Cromwell, died on the island on St. Leonard’s Day, the 6th November 1649. Tradition holds that he was murdered after dancing in a pair of poisoned boots, presented to him under the mask of friendship by a lady sympathetic to the Parliamentarian cause. Three years later, Cromwell's soldiers laid siege on the castle, eventually causing a breech in the south-facing section of the wall. On the 27th April 1653, the garrison holding it surrendered and the fortification was effectively unusable from that time onwards.

The castle, which is circular in plan, stands on a  raised platform of earth that is measured at just over 3 meters (10 feet) above the usual summer level of the lake. Its total height is 17 meters (55 feet), and its internal diameter is 10.5 meters (35 feet), the outer wall thickness being 2.13 meters (7 feet). There are traces of five floors, which were supported by beams, topped by an embattled parapet about 1.82 meters (6 feet) high and .76 meters (2 feet 6 inches) thick. Its internal walls are now missing but the remains of a thick dividing wall in the basement can still be seen. Any decorative window jambs and other dressings have been removed and the whole structure was built of rubble masonry. The original main entrance was about 4.7 meters (15 feet) high off the ground, and a finely-dressed curving arch is now all that remains of it.

Approximately one third of the south-facing curved wall has fallen or was battered down, exposing the building material that makes up its thick walls, allowing for a greater technical understanding of how the castle was erected. 

To the south-east on the mainland, in the townland of Inishconell, once stood the ruins of a building that belonged to the castle.

In 1847, three trumpets were found near the castle and were presented by Lord Farnham, of the nearby Farnham Estate, to the museum of the Royal Irish Academy in Dublin.

In 2023 an extensive clean-up of the site, incorporating the removal of a series of old 20th century staircases and platforms at various heights, as well as an extensive growth of ivy, has allowed for greater details of the castle’s fabric to be seen.

Visit Historic Environment Viewer for more information on Cloughoughter Castle

Protect our Past - Click here to read about the importance of protecting our country’s unique heritage sites

This national monument is protected in accordance with the National Monuments Acts 1930 to 2014