Built sometime in the 15th or early 16th century, this tower house once belonged to the O’Brien clan, the dominant family in the region who controlled much of County Clare for centuries. The castle’s strategic location allowed its inhabitants to oversee the surrounding countryside whilst maintaining defensive positions against rival clans and English incursions.

The structure itself represents a typical example of Irish tower house architecture; a fortified residence designed to withstand sieges whilst providing comfortable accommodation for the local lord and his household. These compact vertical fortresses were the preferred dwelling of the Gaelic and Anglo-Norman nobility throughout late medieval Ireland, combining defensive features like murder holes and battlements with domestic spaces including halls, private chambers and storage areas. Though now reduced to ruins, the remaining walls still show evidence of multiple floors, narrow windows for defence, and the thick limestone construction that helped these buildings endure for centuries.

Today, visitors to Killinaboy can explore the castle ruins freely, though care should be taken as the structure is unsupported and potentially unstable. The site sits near the 12th-century Killinaboy Church, creating an evocative historical landscape that speaks to the long continuity of settlement in this part of Clare. Together, these monuments offer a tangible connection to medieval Ireland, when local chieftains ruled from stone towers and the rhythms of rural life revolved around these centres of power and protection.