Built by the O’Madden clan, who controlled this part of east Galway for centuries, the tower house follows the typical design of Irish fortified residences from the period; a rectangular stone structure rising four storeys high, with thick walls designed to withstand both siege and the harsh Atlantic weather. The castle’s strategic position allowed the O’Maddens to oversee their lands whilst maintaining defensive capabilities, complete with murder holes above the entrance and narrow arrow loops that still pierce the weathered limestone walls.

The castle witnessed significant upheaval during the Cromwellian conquest of Ireland in the 1650s, when many such strongholds were deliberately destroyed or left to decay. Unlike grander castles that were maintained or restored, Kilcooly fell into disuse by the 18th century, becoming part of the rural landscape as local farmers incorporated its stones into field walls and outbuildings. What remains today is largely the main tower, though careful observation reveals traces of a bawn wall that once enclosed a courtyard, and the foundations of what may have been additional domestic buildings.

Today, Kilcooly Castle sits quietly in the Galway countryside, accessible via a short walk through farmland (with landowner permission). The structure, whilst roofless and partially collapsed on its eastern side, still displays fascinating architectural details including a carved stone fireplace on the second floor and the remains of a spiral staircase built into the thickness of the walls. These tower houses, once numbering in the thousands across Ireland, represent a uniquely Irish response to the social and military challenges of the late medieval period, making Kilcooly a valuable, if understated, piece of the country’s architectural heritage.