The structure, measuring 11.6 metres northeast to southwest and 9.4 metres northwest to southeast, survives to two storeys beneath a barrel vault reaching 12 metres in height. It sits at the southeast corner of a rectangular bawn, an old Irish defensive courtyard, which stretches 28 by 22 metres internally and is defined by substantial earth and stone banks on three sides.

The castle’s ownership history reads like a chronicle of Irish rebellion and land disputes. In 1570, it belonged to Brian O’Brien, son of Mahon, but by 1604 had passed to Conor O’Brien, who joined the 1597 rebellion against Elizabeth I and met his death at Killaloe in 1601. His property, including the castle’s upper room, cellar, and orchard, was subsequently granted to John King in 1605. The MacNamaras gained control sometime afterwards, with Teige MacNamara holding half the castle and town until his death in 1634. Following the 1641 rebellion, the property was confiscated and redistributed to various parties, including Paul Strange, described intriguingly as ‘a Transplanted Papist’, along with portions going to John MacNamara and the Earl of Thomond.

Built on a plinth with a robbed base batter, the castle’s uncoursed limestone construction features dressed quoins, though many architectural details have been damaged or removed over time. The ground floor, accessed through a destroyed doorway on the southeast wall, led to a lobby protected by a murder hole, with mural stairs ascending within the walls. The main chamber contained embrasures with lights on three walls, whilst a vaulted souterrain, or underground storage chamber, extends from the northwest wall. The first floor, reached via the internal stairs, was supported on corbels and beam slots, with each wall featuring window embrasures. A garderobe in the projecting tower at the north angle provided essential facilities, whilst unusual narrow grooves beneath the vault hint at construction techniques or functions now lost to time.