This rectangular structure, measuring 13.6 metres east to west and 10.2 metres north to south, features distinctive rounded corners and continuous machicolation supported by slender tapering corbels along most of its upper walls. The tower’s most striking architectural features include large double ogee-headed windows with mullion and transom divisions, likely added during 18th or 19th-century renovations, which punctuate the western wall on each floor above ground level. Inside, visitors would once have entered through a ground-floor doorway on the eastern wall, leading to a lobby that provided access to the main chamber, where a central pillar supports a vaulted roof; a feature probably inserted during later renovations.

The castle’s defensive history is particularly fascinating. Originally the stronghold of the Mac Donogh Mac Carthy sept, it passed to Sir Philip Percival, later Earl of Egmont, after the Mac Carthys joined the 1641 rebellion. Around this time, the tower was fortified with a square bastioned enclosure at each corner, surrounded by a water-filled moat, with an additional circular moat enclosing the tower itself. Though the castle was reportedly “reduced by a battery of cannon” in 1650, the tower shows no obvious battle damage today. A drawing from around 1750 depicts this elaborate double-moat system, though the outer fortification had likely been removed when an unusual octagonal demesne was laid out in the mid-18th century.

The tower has undergone several transformations over the centuries. The Earl of Egmont renovated it shortly before 1750 as a residence for his agent, and it received further updates in 1876, including the addition of a stepped gable and chimney stacks that crown the eastern wall today. The building remained occupied until it was burnt in 1922, after which it was renovated again and now serves as a private residence. While the bastioned fortification has vanished without trace, the circular moat remains visible, though drained since 1876; approximately 40 metres in diameter and 4 metres wide, its edges have collapsed and become covered with sod, yet it still offers a tangible connection to the castle’s defensive past.