This imposing four to five storey tower house, built from a mixture of sandstone and limestone rubble, measures approximately 9.6 metres north to south and 11.75 metres east to west. The castle’s thick walls, reaching 2.6 metres at the base with a pronounced batter extending 4 metres high, speak to its defensive purpose. Originally entered through a pointed doorway elevated above ground level in the eastern wall, complete with a yett-hole for additional security, the structure has been modified over time with additional doorways inserted at ground level in the northern and western walls.

The castle’s history is deeply intertwined with the Butler family, who held sway over this strategic location for generations. Records from 1525 mention Richard and Theobald Butler, sons of William Butler, as Lords of ‘Powyllykyri’, whilst the Civil Survey of 1652-4 notes that Richard Butler held the property as his mansion house in 1640. The Butlers weren’t always popular neighbours; in the sixteenth century, the people of Clonmel protested against Walter Butler’s plundering of their river boats. The castle’s most dramatic moment came during the Cromwellian conquest when Adjutant General Sadler besieged the fortress in 1650. When the defenders refused to surrender, he stormed the castle, putting more than thirty to the sword, whilst those who remained obstinate were burned alive within its walls.

Following this brutal assault, the Commonwealth repaired and garrisoned the castle, though ownership passed to James Rathorne during the Cromwellian confiscations; his family would later be attainted by the Parliament of James II in 1689. The interior retains many original features including two vaulted floors and the characteristic zigzag stairway typical of Irish tower houses. Natural light enters through an evolution of window styles; flat, round, and ogee-headed single lights pierce the lower floors, whilst elegant ogee-headed two-light windows with sandstone surrounds illuminate the top floor. Angle-lights at various corners likely mark the position of the mural stairs, and a garderobe chute exits the southern wall, a practical reminder of medieval daily life. Restored in the 1970s, this remarkable survivor is now a private residence, its thick walls continuing to shelter inhabitants as they have for nearly five hundred years.