The location sits within a moated enclosure, a defensive feature that would have surrounded the original structure with a water-filled ditch. Historical records show the castle was standing in 1574, when it belonged to an individual known as Shane ne Moy, though the building itself likely dated from an earlier period.

By the time the Ordnance Survey teams visited the site in the 1820s and 1830s, the castle had already fallen into significant decay. Their field letters, compiled during the great mapping project of Ireland, noted that only the foundations could still be traced on the ground. Today, even those foundations have vanished beneath centuries of agricultural activity, leaving just subtle changes in the landscape to hint at the site’s medieval past.

The archaeological significance of Cloonigny Castle has earned it protection as National Monument 563, placing it under state ownership and care. Though visitors won’t find dramatic ruins or towering walls, the site offers a glimpse into how the Irish landscape holds memories of its turbulent history, with even the most modest field potentially concealing the remains of once-important strongholds. The earthworks that survive represent the last physical traces of a fortification that would have controlled this portion of north Galway for generations.