This tower house, measuring roughly 11.3 metres square with walls two metres thick, was constructed from roughly coursed limestone rubble. Though time and destruction have left the structure poorly preserved, with no visible architectural features remaining, the castle’s footprint tells a story of medieval fortification that cleverly incorporated much older defensive earthworks.

The castle appears to have been built strategically within an existing ringfort, transforming the ancient circular enclosure into a ready-made bailey; essentially a defended courtyard for the tower house. This clever reuse of prehistoric fortifications was common practice in medieval Ireland, where builders recognised the defensive advantages of these earlier structures. The surrounding earthwork may date back centuries before the castle itself, though some historians suggest it could have been contemporary with the tower house, perhaps supporting a timber palisade that served as a defensive bawn wall.

Historical records indicate that Clonoghil Castle met its demise in 1642, when Irish forces burned it during the tumultuous period of the Irish Confederate Wars. Archaeological investigation in 2006, conducted as part of pre-development assessment work near the site, yielded little additional information about the castle or its surroundings. Today, these weathered ruins serve as a quiet testament to the layers of Irish history, where medieval lords built upon ancient foundations, and where centuries of conflict have left their mark on the landscape.