The enclosure at Derreennageeha is not dramatic to look at; most of the wall has collapsed, and what remains rises no higher than a metre, its lower courses moss-covered and half-swallowed by the surrounding peat. Yet the scale of what it once described is considerable: roughly 65 metres east to west and 55 metres north to south, a roughly circular area that would have enclosed a meaningful patch of ground, even if the purpose of that enclosure is now harder to read than its outline.

Drystone enclosures of this kind, built without mortar by laying shaped and unshaped stone together in courses, are found across Kerry and much of the Irish west, typically associated with early medieval settlement and agriculture, though dating individual examples without excavation is rarely straightforward. What makes Derreennageeha particularly legible as a former place of habitation is the presence of hut sites within and near the enclosure. One sits in the northern quadrant of the interior; another lies roughly ten metres outside the northern wall. These hut sites, the structural remains of small circular or oval dwellings, suggest that the enclosure functioned not simply as a field boundary but as part of a small domestic complex, the kind of farmstead arrangement that was once common across upland Kerry before the land was given over to forestry and bog.

The plantation that now covers the site both preserves and obscures it. Forest debris has buried much of the enclosing wall, and the uneven, north-facing slope makes the ground awkward underfoot. The larger boulders from the lower wall courses still protrude above the bog surface, which gives a rough sense of the enclosure's perimeter even where the wall itself has spread and fallen. It is the kind of place where the archaeology announces itself gradually, as shapes in the ground rather than structures in the conventional sense.