Roughly thirty metres across, it sits in a flat, lush valley meadow with a stream running nearby, and at ground level it leaves no visible trace whatsoever. Its existence is known only because an aerial photograph, reference Air Corps V.312/3077-6, caught what the eye on the ground cannot: the faint signature of a circular form pressed into the landscape, detectable from above through crop marks or soil variation, but otherwise entirely absent from ordinary experience.

This kind of site is not unusual in Irish archaeology in the abstract, but the particular quality of this one is its completeness of concealment. Circular enclosures of this type are generally understood to be the remains of ringforts, which were the most common form of rural settlement in early medieval Ireland, typically consisting of a bank and ditch enclosing a domestic space. At Garryduff, whatever bank or ditch once defined that circle has been so thoroughly levelled, absorbed, or eroded that the meadow shows nothing. The aerial photograph alone preserves the knowledge that something was once deliberately bounded here, in a quiet valley with ground sloping gradually toward the north-northwest and a stream flowing southwest not far off.