It is a rath, the Irish term for a ringfort, the most common type of early medieval monument in Ireland. Thousands were built across the country between roughly the fifth and twelfth centuries, typically as enclosed farmsteads for a single family or small community. This one is modest in scale but complete enough in form to read clearly: a roughly circular enclosure about twenty-nine metres in diameter, defined by an earthen bank standing some 1.7 metres high, with a shallow external fosse, or ditch, still visible to the south-west.

The bank and parts of the interior have been planted with trees over the years, which is not unusual for these sites. Landowners have long recognised that ringforts, however ancient, make practical field boundaries, and the raised earthworks often end up hosting scrub or hedgerow vegetation that would be difficult to clear. More intriguing is the possible souterrain recorded within the interior. Souterrains are underground passages or chambers, typically stone-lined, that were constructed during the early medieval period, most likely for storage and possibly for refuge. Their association with ringforts is well established across Ireland, and their presence at a site often suggests a degree of permanence and investment in the original settlement. Whether the underground feature at Knockrour is a true souterrain or a natural depression of some kind remains uncertain, but the possibility adds a layer of complexity to what might otherwise appear to be a simple earthwork.