Dunlough Castle

When the first Norman soldiers and settlers reached Ireland in 1169, the O'Mahonys were the declining but still powerful princes of Eóganacht Raithlind, holding roughly the country from Cork City west to Mizen Head. Their regional prominence had been cut back since the MacCarthy dynasty came south from Tipperary in the early 12th century, and it faded faster still as the Normans took hold of southern Ireland. The McCarthys and the O'Briens were their chief Irish rivals and allies by turns; all of them were militarily outclassed by the Normans who followed in the wake of Henry II's invasion.

In 1177 Henry granted "the kingdom of Cork" to the Cambro-Norman knights Robert Fitz-Stephen and Milo de Cogan. De Cogan received the lands of west Cork and began a push towards the Atlantic that drove the regional families from their holdings in central Cork. The O'Mahonys, under their chieftain Donagh "the Migrator", settled at the furthest point of all, the tip of the Mizen Peninsula, and in 1207 Donagh founded Dunlough on the cliffs at its northern end — one of the oldest castles in Ireland.

The O'Mahonys held Dunlough for some four hundred years, until the British crown confiscated the castle in 1627.

Dunlough is three fortified towers set across the isthmus joining Three Castles Head to the mainland, linked by a wall running more than a hundred feet from the western cliffs to the shore of a lake that appears to be man-made. A wall of the same period dams the lake's eastern shore, holding its water back from the drop into Dunmanus Bay several hundred feet below. Each keep stands three storeys, the usual height for rectangular towers of the day, and each is of a distinct design and rather smaller than the solitary towers more typical of the region. The eastern keep was probably the gate tower; the western, the largest, most likely housed the bulk of the inhabitants; the central one added lookout and storage and stiffened the connecting wall, in the manner of the sub-towers of larger Norman castles. The connecting wall is mostly fallen now, though it stands about 15 feet in places, and the only route to the towers is from the south, across private farmland.

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." No attack on Dunlough is recorded, and it is not known whether any army ever attempted one.

Dunlough was raised in dry stone masonry, common in earlier Irish building but unusual among the castles of this coast, which were put up in later years with wet mortar and sand; the method accounts in part for the castle's deterioration. Its western keep carries a feature common to O'Mahony castles: a second-storey door usually set directly above or just beside the first-storey entrance, probably reached by a removable wooden ladder. The third storey, here as at other O'Mahony keeps, was a stone floor serving as the banquet and gathering hall, a common feature of early Norman keeps. The simple rectangular towers of Dunlough foreshadowed the castles built along both shores of the Mizen in later years, many of them O'Mahony keeps, plain and unornamented.