The site at Corrinshigo occupies the east-facing spine of a ridge running roughly west-northwest to east-southeast, a position typical of early medieval ringforts in Ireland, which were commonly sited to command views and signal presence across the surrounding landscape. What lifts this particular example out of the ordinary is a long, narrow depression running south from the centre of the enclosure to a gap in the perimeter, with a spur branching west just inside the bank. The measurements are precise enough to be suggestive: fourteen metres long, just under four metres wide, half a metre deep, with the spur adding another eight metres. The working interpretation is that this may be a souterrain, an underground stone-lined passage or chamber typically associated with early Irish settlement sites and used variously for storage, refuge, or ventilation. No stonework is currently visible at the surface, which leaves the question open.

The enclosure itself is oval, measuring roughly 31 metres along its longer axis and 21 metres across, with an earthen bank that survives in varying condition. On the northeast it retains a base width of nearly five metres and an external height of around three metres, though much of the rest has been reduced to little more than an overgrown scarp. A ramp entrance, 2.4 metres wide at its base, opens to the east, and an outer berm curves around the south and southwest before merging into a farm lane. That blurring of ancient boundary into working agricultural infrastructure is a common fate for earthworks in the drumlin country of south Ulster, where the rounded glacial hills have been farmed continuously for centuries and the older features of the land tend to survive only in fragments.