No earthen banks survive above ground, no obvious ditch breaks the surface. What remains is a cropmark, a faint circular trace roughly twenty metres across that becomes legible only from the air, when differences in soil moisture or crop growth betray the buried outline of an ancient enclosure.

Ringforts, known in Irish as raths, were the most common form of rural settlement in early medieval Ireland, typically consisting of a circular area enclosed by one or more earthen banks and external ditches. The feature at Harristown appears to have had a single fosse, meaning a single encircling ditch, which places it among the simpler examples of the type. The site sits on level ground, and aerial photographs show it connected to the cropmarks of curvilinear field drains, suggesting that the landscape around it has been worked and reworn over a very long time. The circular enclosure was identified on earlier aerial photographs and confirmed again on digital aerial photographs taken in July 2006, by which point the earthworks themselves had long since been ploughed flat or otherwise levelled into the surrounding farmland.

There is something quietly vertiginous about a site like this. A community once organised its domestic life within that twenty-metre circle, and the only evidence still legible is a shadow in a crop, visible to a camera mounted in a low-flying aircraft on a dry summer morning.