This rectangular structure, measuring roughly 14 metres north to south and nearly 6 metres east to west, forms part of a larger complex that may once have been a fortified bawn; a defensive courtyard typical of medieval Irish settlements. Today, only portions of the north gable wall and eastern side wall survive, built from local rubble limestone masonry averaging just under a metre thick.

The building’s internal layout reveals its defensive purpose. A substantial cross wall, nearly two metres thick, divides the structure into two distinct spaces: a northern guard chamber and a southern barrel vaulted passageway. The guard chamber, which has collapsed to a single storey, features a blocked arrow loop in its eastern wall; a reminder of its military function. Above the vaulted passage, fragments of a second storey remain, including traces of an intramural staircase built into the dividing wall and supported by an internal squinch, a clever architectural feature that allowed medieval builders to create corners where walls met at awkward angles.

The gatehouse doesn’t stand alone in this historic landscape. Just 40 metres to the west northwest lie the ruins of a religious house, possibly once belonging to the Knights Hospitallers, whilst a similar distance to the north northwest, a medieval church and its accompanying graveyard complete this remarkable cluster of medieval buildings. Together, these structures paint a picture of a once thriving religious and defensive complex, now largely reclaimed by nature and reduced to overgrown stone outlines in the Kildare countryside.