The enclosure is substantial, roughly 66 metres north to south and 59 metres east to west, making it comparable in scale to many of the ringforts that are scattered across the Irish midlands and south. A ringfort, to give the general type its name, is typically a circular or oval area enclosed by one or more earthen banks and ditches, most commonly dating from the early medieval period and associated with farming settlements or defended homesteads. What makes Kilroe slightly unusual is the way its two halves tell different stories about what time and land use do to such places.

The western half of the enclosure still carries its bank, an earthen field boundary about 1.2 metres wide, with stone revetting set into the outer face to reinforce it. Stone revetting, the practice of facing an earthwork with stone to stabilise it, is a detail that speaks to some care in the original construction. The interior ground level rises slightly, a feature sometimes associated with accumulated occupation deposits or deliberate raising of the living surface. The eastern half, however, has been levelled, its original bank gone. What remains to mark it is a low scarp, barely 0.42 metres high, and the faint trace of an outer fosse, a shallow external ditch only 0.17 metres deep and 2.6 metres wide, just visible enough to confirm where the boundary once ran. The enclosure sits on fairly flat terrain with a gentle eastward slope, the kind of unspectacular landscape that tends to preserve such things quietly for centuries, until ploughing or field improvement finally gets to them.