The circular earthwork here, a possible rath or enclosed farmstead of early medieval type, has been levelled, and what remains is essentially the ghost of a boundary: a slightly raised circular area, roughly 30 metres north to south and 27 metres east to west, that can still be traced across improved pasture if you know what you are looking for.

A rath was a ringfort, the most common form of rural settlement in early medieval Ireland, typically consisting of a raised circular bank enclosing a farmstead or family compound. At Castlebarnagh, the 1838 Ordnance Survey six-inch map recorded it as an embanked enclosure, with a road skirting its north-western arc. By the time the 1930 edition was drawn, the road had shifted to clip the north-eastern side, and a field boundary had taken up position along the west. That later boundary is, in a sense, all that is left with any real substance. Remnants of the original enclosing scarp survive at the west-northwest, standing to about one metre in height where they have been absorbed into the field wall, the old earthwork quietly doing duty as modern infrastructure.

The site sits on a ridge above the surrounding land, and whatever else has been lost, the position still makes itself felt. The views open out particularly to the north and north-east, a reminder that whoever chose this ground to live on, probably well over a thousand years ago, understood something about watching over a landscape.