Known locally as An Caiseal (Tc Maol Mosóg), the site appears on Ordnance Survey 6-inch maps simply marked as a 'Fort', though its true history runs much deeper. The circular platform, measuring 33.5 metres across, rises between half a metre and 3.3 metres above the surrounding landscape, creating a distinctive profile against the Donegal countryside where good farmland meets rougher terrain.

The fort's construction reveals the resourcefulness of its builders, who incorporated stones into the platform's edges to create a defensive structure that would have once dominated this strategic location. Unfortunately, many of these original stones have since found their way into the adjacent field walls, a common fate for ancient monuments throughout Ireland as generations of farmers repurposed readily available building materials. What remains today is a subcircular earthwork that still commands respect, even in its diminished state.

This site forms part of County Donegal's rich archaeological landscape, documented in the comprehensive 1983 survey by Brian Lacey and his team of archaeologists. Their work catalogued field antiquities spanning from the Mesolithic period through to the 17th century, placing this ringfort within a broader context of human settlement and fortification in the region. The fort's position in the River Aighe valley would have offered its inhabitants both defensive advantages and access to varied agricultural resources, making it an ideal location for a early medieval settlement.