A rath, the Irish term for a ringfort, is a circular earthen enclosure built during the early medieval period, typically between the fifth and twelfth centuries, and used as a defended farmstead. Thousands once dotted the Irish countryside. This one at Loumanagh has been largely levelled, yet its outline has not entirely surrendered to the surrounding farmland.

By 1842, when the Ordnance Survey recorded it on their six-inch map, the site was already rendered only as a hachured circle, a cartographic convention indicating an earthwork, with a diameter of roughly twenty metres. It sat at the junction of three fields, a position that may partly explain why it was gradually absorbed into the working landscape around it. What survives today is a roughly circular area, measuring approximately twenty-five metres north to south and twenty-four metres east to west, defined along its northern arc by a low scarp reaching about forty-three centimetres in height. Along the northwest to north-northeast section, an earthen field boundary, standing between one and a half and one point eight metres externally, likely incorporates what remains of the original enclosing bank. The interior is slightly raised and slopes gently southward, towards the sun, which may well reflect the deliberate choice of a south-facing slope for the original settlement. A field boundary that once extended westward from the site has itself since been levelled, removing one of the last visible relationships between the rath and the field system that grew up around it.