This cashel, measuring approximately 28 metres across, consists of a circular defensive wall built from carefully placed boulders with rubble fill. Though the centuries have taken their toll on the interior, causing considerable collapse and disturbance, the outer perimeter of the wall remains remarkably intact, allowing visitors to trace the original footprint of this ancient fortification.

The structure sits just below the crest of a hill overlooking the River Swilly, a strategic position that would have offered both defensive advantages and access to fertile agricultural land. The steep slopes leading down to the river would have provided natural protection on one side, whilst the elevated position allowed inhabitants to survey the surrounding landscape for approaching visitors or potential threats. A gap in the western section of the wall may have served as an original entrance, though its current state, cutting across the boulder line, suggests it might be a more recent modification.

These ringforts, known locally as cashels when built primarily of stone, were typically constructed between the 5th and 12th centuries AD and served as fortified homesteads for farming families of some status. The substantial nature of the stone construction at Ballygawley, combined with its commanding position above the Swilly, suggests this was home to a family of considerable local importance. Today, the site forms part of Donegal's rich archaeological landscape, documented in the county's comprehensive archaeological survey and offering a tangible connection to the lives of those who shaped this corner of Ulster over a millennium ago.