It is a ringfort, or rath, one of the thousands of circular enclosures built across Ireland during the early medieval period, typically between the fifth and twelfth centuries, and used as defended farmsteads or the residences of local lords. What makes this one worth pausing over is the precision of its survival: the earthen bank still stands a metre high on the exterior, its outer fosse, a defensive ditch dug around the perimeter, still clearly defined at the north-east, with the ditch walls and base measurable to within centimetres.

The enclosure is defined by an earthen bank roughly three metres wide, with the interior standing about half a metre above the original ground level and the exterior face rising a full metre. Beyond that bank runs the fosse, which retains an internal depth of 2.3 metres, a figure that gives a real sense of the effort involved in its original construction. At the south-east, an entrance gap survives, now somewhat wider than it would originally have been, though it is thought to be genuinely ancient rather than a later break. The drumlin ridge on which the fort sits, one of the glacially deposited elongated hills that roll across much of Monaghan and south Ulster, would have given whoever occupied the site a clear view over the surrounding low ground. One small change has occurred in the recent past: a field bank that ran just to the west of the enclosure, visible on older Ordnance Survey aerial photographs, had been removed by the time surveyors revisited the site after 1995.