Dunlough Castle

Dunlough Castle, standing atop the cliffs at the northern tip of the Mizen Peninsula, looks at the Atlantic Ocean from the extreme southwest point of Ireland. Founded in 1207 by Donagh O’Mahony, Dunlough is one of the oldest Norman castles in southern Ireland and an interesting example of Norman architecture and dry stone masonry.

Dunlough Castle is a series of three fortified towers, or keeps, which stand almost invisibly upon the isthmus connecting “Three Castles Head” with the mainland. The only route of access is from the south across private farm land. The towers are connected by a wall spanning more than one hundred feet from the western cliffs to the shores of an apparently man-made lake. The wall is mostly fallen today; yet in places it stands approximately 15 feet (4.6 m). At the eastern shore of the lake, a wall from the same period serves as a dam, preventing the lake's water from pouring over the cliffs into Dunmanus Bay several hundred feet below. Passage around the eastern shore of the lake is awkward; while the castle and wall block the western shore. A small footpath between the westernmost ruins and the 400-foot (120 m) cliffs allows access to the towers and rocky cliffs beyond. As one writer has observed, "To an invading army, the cliff’s edge, the defensive wall, the lake and the sternly inaccessible approach would have made the castle appear impregnable." It is not known if Dunlough was ever attacked.

At the time the first Norman soldiers and settlers arrived in Ireland in 1169, the O'Mahonys were the declining but still powerful princes of Eóganacht Raithlind, occupying approximately the area from Cork City west to Mizen Head. Their regional prominence had been diminished greatly since the MacCarthy dynasty had come south from Tipperary in the early 12th century, and faded even more rapidly as the Normans took hold of southern Ireland. Their primary Irish rivals (and allies) were the McCarthys and the O'Briens. But all these groups were militarily outclassed by the Normans who followed in the wake of King Henry II's initial invasion.

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