The site is a rath, the Irish term for a ringfort, which was the most common form of rural settlement in Ireland from roughly the fourth to the twelfth centuries. Most were homesteads, enclosing a family's dwelling and outbuildings within a raised earthen ring. This one at Parsonstown is larger than many, with a roughly sub-circular enclosure measuring approximately 42 metres north to south and 37 metres east to west.

What survives here is a double-banked example, meaning two earthen banks encircle the interior with a fosse, or ditch, running between them. The inner bank remains substantial, though it carries several gaps along its circuit. The fosse itself has been partially absorbed into later field boundaries, and in those sections it appears to have been artificially steepened, its original profile altered by whoever set the field fences. The outer bank is considerably lower. At the eastern side, a narrow entrance gap roughly two and a half metres wide is accompanied by a slight causeway crossing the fosse, the original threshold of the enclosure still legible in the ground. Inside, faint traces of cultivation ridges run across the sloping interior, suggesting the enclosed space was put to agricultural use at some point after the ringfort fell out of residential occupation. Two modern field fences cut across the monument, one running north to south across the western side and another east to west across the southern portion, the working landscape of later centuries laid directly over the earlier one. A second ringfort lies approximately 125 metres to the north-east, a reminder that such sites were rarely isolated; families and communities clustered within sight of one another across the Irish midland countryside.