Built sometime in the 15th or early 16th century, this tower house represents the type of fortified residence favoured by Gaelic and Anglo-Norman families during a period when local conflicts demanded both comfort and security. The castle’s rectangular plan and thick walls, typical of Irish tower houses, would have provided its inhabitants with a secure base whilst maintaining control over the surrounding lands.

The structure follows the classic tower house design with multiple storeys accessed by a spiral staircase built into the thickness of the walls. Murder holes, narrow window loops, and a machicolation over the entrance demonstrate the defensive considerations that went into its construction. Inside, the castle would have contained a great hall for entertaining and conducting business, private chambers for the family, and storage areas at ground level. The remains suggest it originally stood four or five storeys high, with a wall walk and battlements crowning the structure.

According to historical records documented by Risteárd Ua Cróinín and Martin Breen in their comprehensive survey of Clare’s castles and tower houses, Coolreagh Castle likely belonged to a branch of the O’Brien family, the dominant Gaelic dynasty in the region. The castle’s strategic position allowed its owners to monitor movement through the local landscape whilst maintaining connections with other O’Brien strongholds throughout County Clare. Though now roofless and partially ruined, the castle’s surviving walls continue to dominate the site, offering visitors a glimpse into the turbulent world of late medieval Ireland when such fortifications were essential for survival and status.