This circular earthwork, measuring 42 metres across, varies in height from just 10 centimetres on its western side to 60 centimetres elsewhere, creating a raised platform that once likely supported a defensive settlement. The fort's centre dips slightly inward, a common feature in these structures that often indicates where wooden buildings once stood, whilst traces of what may have been an entrance can still be detected on the western side.

Today, the site bears the marks of centuries of agricultural use; a field boundary and drainage ditch cut straight through the monument from north to south, evidence of how the landscape has been continuously worked and reworked over time. The ringfort's strategic position becomes clear when you consider its setting: positioned on the crest of a hill with ground sloping away to the north and east, it would have offered its inhabitants commanding views of the surrounding countryside, essential for both defence and monitoring agricultural lands.

Ringforts, or raths as they're known in Irish, were the homesteads of farming families from roughly 500 to 1200 AD. This example at Rathglass, though weathered and partially levelled by time and farming activity, remains an important piece of Donegal's archaeological landscape, documented in the comprehensive Archaeological Survey of County Donegal first compiled in 1983. Like thousands of similar sites scattered across Ireland, it serves as a tangible link to the people who shaped this landscape long before modern field systems and drainage works altered its ancient contours.