The castle’s remains, documented by researchers Risteárd Ua Cróinín and Martin Breen, consist primarily of a rectangular tower house typical of the late medieval period. Built sometime in the 15th or 16th century, the structure would have served as both a defensive fortification and residence for a local lord, combining practical military architecture with the domestic needs of a noble household.

The castle’s strategic position in County Clare placed it within the sphere of influence of several powerful Gaelic families, particularly the O’Briens who dominated much of the region during the medieval period. Like many tower houses of its era, Rathfolan would have been a symbol of authority in the local landscape; its thick walls and narrow windows designed to withstand sieges whilst providing a secure base for controlling the surrounding territory. The structure likely featured the typical arrangement of vaulted chambers on the ground floor for storage, with residential quarters above, accessed by a spiral staircase built into the thickness of the walls.

Today, what remains of Rathfolan Castle offers visitors a glimpse into the turbulent history of medieval Ireland, when such fortified dwellings dotted the countryside. Though time and weather have reduced it to ruins, the surviving stonework demonstrates the skill of medieval masons and the enduring nature of these defensive structures. The castle’s weathered walls continue to stand as testament to an era when control of land meant survival, and every local lord needed a stronghold to call home.