It is a rath, the Irish term for a ringfort, the kind of enclosed farmstead that was built in their thousands across Ireland during the early medieval period, roughly between the fifth and twelfth centuries. Most raths occupied productive lowland, close to good soil and water. This one, at around twenty metres across, occupies boggy upland terrain, which raises the obvious question of why anyone chose to build here at all.

The structure is defined by an earth and stone bank, modest in height, standing about half a metre on its outer face and somewhat less on the inside. Around the south-west and south-east, an external fosse, a defensive ditch, cuts down into the underlying rock to a depth of nearly one and a half metres, though it becomes shallower as it runs elsewhere around the perimeter. A second bank runs from the west-south-west towards the east, and exposed rock outcrops fill the gap running back the other direction. The entrance, about two metres wide, faces east-south-east and is stone-faced on its southern side, a detail that suggests some care in its construction. Despite the boggy surroundings, the interior slopes gently down towards the north-east and remains noticeably drier than the land outside the banks, which may help explain the choice of location. That small advantage in drainage, combined perhaps with the defensibility of a rocky slope, could have made this an acceptable, if marginal, place to live.

The gorse that now covers the banks makes the earthworks harder to read at ground level, but the fosse where it cuts into rock outcrop to the south gives a clear sense of the effort involved in carving this enclosure out of the hillside. The name Doire Na Sagart translates roughly from Irish as the oak wood of the priests, a place-name that hints at a longer and more layered history than the rath alone.