A ringfort, or rath, is an enclosed farmstead of early medieval Ireland, typically dating from roughly the fifth to the twelfth century, where a family and their livestock lived within a banked and ditched perimeter. Thousands survive across the island in varying states of preservation, though many have been levelled by agriculture. This one at Garryroe retains enough of its original form to give a clear sense of how such a settlement once looked from the outside.

The enclosure measures just over 44 metres north to south and about 43 metres east to west. Its bank, built from compact earth and gravel, stands to an external height of just over two metres and is nearly two metres wide at the crest, broadening to more than six metres at the base. A fosse, the outer ditch, runs around the outside, around a metre deep and over three metres wide. The principal entrance appears to have been in the northern quadrant, a gap nearly eleven and a half metres wide that was already recorded on the Ordnance Survey six-inch map published in 1907. A smaller break of about two metres in the south-western quadrant looks like a later intrusion rather than an original feature, and in the western section the bank has been disturbed, leaving a wider and flatter profile than the rest of the circuit. Hazel trees have taken hold along the bank, framing the interior, which is otherwise clear of vegetation.