Locals have long called it Bryan's Fort, though the name is something of a puzzle given what the structure actually is: not a conventional fort in the military garrison sense, but a fortified dwelling, a private residence built to be defended. The distinction matters. This was someone's home, designed with cannon opes and gun loops because the times demanded it.

Colonel Richard Townsend built the place around 1650, a period when settlers of English origin in Munster had every reason to fortify wherever they lived. The structure is modest in scale, with an internal length of roughly eight metres, but it was carefully conceived. A bastioned fort uses angled projections at the corners, each one a bastion, to eliminate blind spots and allow defenders to cover the walls from the sides. Here, all four corners have such projections, two of them on two floors. The south-facing bastions, the ones looking directly over the bay, were equipped with pairs of large openings sized for cannon rather than muskets. A wall walk ran along the south wall, reached by a stone staircase just inside the western door, and doors from that walk gave access to the south-eastern and south-western bastions. The eastern wall retains a poorly preserved gable with a first-floor doorway and fireplace, which suggests habitation rather than purely military use, though the missing western gable raises questions about whether the whole structure was ever roofed. The fort was attacked several times in 1690, a year of intense conflict across Ireland during the Williamite War, and those events are recorded in detail by a later member of the Townsend family.