Whatever entrance once existed has been filled in, leaving a path that arrives at a solid wall of earth, a quiet architectural puzzle sitting in otherwise ordinary pasture above a north-facing slope.

The site is a rath, the Irish term for a ringfort, a type of enclosed farmstead used throughout Ireland roughly between the fifth and twelfth centuries. Thousands survive across the country in varying states of preservation, but this one at Ballynahalisk has some specific features worth noting. The roughly circular enclosure measures 22 metres across in both directions and is defined by an earthen bank faced with stone, meaning the inner slope of the bank is reinforced with masonry to hold its shape. Around the outside runs a fosse, a defensive ditch, some eight metres wide and about 0.8 metres deep. The bank itself rises around a metre above the interior ground level and slightly higher on the external face. Trees have been planted along the bank, which is common on such sites in the Irish countryside, sometimes as a deliberate act of boundary marking, sometimes simply because livestock avoid the elevated ground. Quarrying has taken place both around the perimeter and within the fosse itself, which will have disturbed the original profile of the earthworks to some degree.