The structure measures 6.7 metres from northwest to southeast and 4.7 metres from northeast to southwest, with its most striking feature being a round-arched entrance on the southwestern side. Just 70 metres southeast sits the main house, creating a defensive arrangement typical of Irish medieval and post-medieval estates.

The entrance itself spans 2.8 metres wide and leads through a barrel-vaulted passage, a construction technique that provided both strength and an imposing sense of arrival. A doorway built into the southeastern pier opens onto a newel staircase; these spiral stairs wind upward to reach the chamber above. This upper room features single window openings on both the northwestern and southwestern walls, allowing light to filter in whilst maintaining the building’s defensive character.

Though modest in scale, the gatehouse represents the kind of fortified domestic architecture that once dotted the Irish countryside, serving both practical and symbolic purposes. These structures controlled access to estates whilst projecting the status and authority of their owners. The proximity to the River Blackwater would have been strategically important, providing both a natural boundary and a vital water source for the estate’s inhabitants.