Measuring roughly 212.5 metres along its north-east to south-west axis and about 180 metres north to south, it is big enough to have contained a small community, yet much of what once defined its boundary has vanished. Where the enclosing elements do survive, they take the form of a scarp, a low step in the ground, with traces of an earthen bank running from the north around to the east-south-east. A ditch, known in archaeological terms as a fosse, appears at the north and reappears intermittently as far as the south-west. At the north-east, there is a gap of nearly 28 metres where nothing survives at all, and the western arc has disappeared entirely beneath the landscape.

What makes the site more than an eroded earthwork is the cluster of evidence gathered around it. A cashel, a type of early medieval stone enclosure typically associated with settlement or ecclesiastical use, lies within the complex, and a watermill sits immediately to the south-west. Adjoining the main enclosure at the south-east is a smaller, roughly oval annexe of around 80 metres, itself defined by an earthen bank and external fosse. Annexes of this kind are sometimes interpreted as subsidiary enclosures serving a specific function within a larger monastic layout. The place-name Kilcornan is also telling: the element "kil" derives from the Irish "cill", meaning a church or early religious settlement, and when read alongside the physical remains and the associated cashel, the evidence points consistently towards an early ecclesiastical settlement of some significance, even if no church structure now stands above ground.

The enclosure is crossed by later field boundaries that cut through its interior, a reminder that agricultural life continued here long after the original settlement was abandoned or forgotten. Much of what was once a coherent landscape of religious activity now requires some patience to read, as the surviving earthworks are subtle and the boggy terrain does not give up its outlines easily.