Known locally as Raithnigh in the townland of An Cheathrú Chaol, this defensive structure appeared on the first and second editions of the Ordnance Survey’s 6-inch maps, marked simply as ‘Fort’. Today, no visible traces remain of what would have been a circular earthwork enclosure, likely dating from the early medieval period when such fortifications dotted the Irish countryside.

The fort’s disappearance from both the physical landscape and later maps tells a familiar story of Ireland’s archaeological heritage. Many ringforts, which once numbered in the tens of thousands across the island, have been lost to agricultural improvements, particularly during the 19th and 20th centuries when mechanised farming transformed the rural landscape. The low-lying position near the bay suggests this site may have been chosen for its proximity to maritime resources and trade routes, whilst the flat terrain would have made construction easier, though perhaps less defensible than hilltop locations.

The Archaeological Survey of County Donegal, compiled in 1983, recorded this lost monument as part of a comprehensive effort to document the county’s field antiquities from the Mesolithic period through to the 17th century. Though the physical fort has gone, its inclusion in early Ordnance Survey mapping and subsequent archaeological records ensures that this piece of Donegal’s medieval landscape isn’t entirely forgotten, serving as a reminder of the countless archaeological sites that have been erased from Ireland’s countryside over the centuries.