This is a rath, the Irish term for a ringfort, the single most common field monument in the Irish landscape. Ringforts were typically enclosed farmsteads of the early medieval period, roughly 500 to 1000 AD, where a family and their animals lived within a protective bank and ditch. Most were built from whatever the local ground offered, which is why this one mixes an earthen bank with loose stones and boulders along part of its circuit.

The enclosure measures about 36 metres east to west and 34 metres north to south, making it a fairly typical example in terms of scale, though its construction is notably varied around the perimeter. The bank running from the north-east to the south-south-west is the most substantial, with an internal height of around 2.4 metres and an external height of roughly three metres. Along the opposite arc, from the west-south-west to the north-east, the bank is lower and topped with loose stone and boulders rather than compacted earth alone. There is a further low rise continuing from the north-east around to the east-north-east. The original entrance appears to have been on the south-west side, where an eight-metre gap breaks the bank, orientated towards the valley below and the rise of Gortnalour Hill beyond.