This modest fortification, measuring just 3.5 metres east to west internally, stands as one of two ‘decayed castles’ mentioned in the Civil Survey of 1654-6, when the parish was divided amongst several proprietors including James, Earl of Ormond, and various members of the Butler and Bourke families. The tower house’s proximity to both the bailey and a nearby church, some 190 metres to the north-northeast, suggests it once played a vital role in the defensive and administrative landscape of medieval Knockgraffon.

The structure itself tells a story of gradual decline through its surviving walls. When surveyed in 1840, the north wall stood at roughly 4.5 metres high whilst the west wall reached 6 metres, both featuring different thicknesses that hint at various construction phases or defensive priorities. Today, only these two walls and a fragment of the eastern wall remain standing, reaching up to second floor level but heavily shrouded in ivy. The ground floor preserves a few telling details: a flat-headed window with splayed embrasure in the western wall, still bearing traces of its original render, and a garderobe chute exiting through the northern wall, a reminder of the practical considerations of castle living.

Archaeological evidence suggests this was once a functional, if compact, defensive residence. Corbels that once supported upper floors are still visible, and photographs from 1952, taken before the ivy took hold, reveal what appears to be an additional loop window at first floor level. Built from locally sourced limestone with occasional sandstone, the walls were originally harled on the exterior and feature a protective base batter on the north side. Though now largely collapsed and overgrown, this small tower house remains an evocative fragment of Knockgraffon’s medieval past, when even modest fortifications played crucial roles in controlling and defending the surrounding countryside.