Roughly twenty metres long and fifteen metres wide, flat-topped and gently slumped on its western and northern sides, it reads at first glance as a natural feature of the machair, the thin, wind-scoured grassland over sand that characterises the Atlantic fringe of Ireland's west coast. What gives it away are the stones: a cluster of large upright slabs pushing out from the mound's western edge, and others lying flat, partly swallowed by the turf, suggesting the bones of a structure that has long since lost its shape above ground.

The mound is understood to be a habitation site, a place where people once lived, though the record is quiet on exactly when or for how long. What it does preserve, intermittently visible in the eroding western edge, is a midden, the compacted remains of domestic waste, typically shells, animal bone, ash, and broken objects, that accumulates wherever people eat and discard over extended periods. Middens are among the most informative deposits an archaeologist can encounter, because they hold the residue of daily life rather than ceremonial or elite activity. A ruined drystone field wall crosses the mound's eastern edge and encloses one of several small, roughly rectangular field plots that extend to the east; these are considered later in date than the mound itself, suggesting the landscape here was reorganised at some point after the original occupation. A further possible habitation site and associated midden lie about thirty metres to the south, hinting that this corner of the island once supported more than a single household.

Inishkea South is uninhabited today and access is by boat only, which means the site sits largely undisturbed in the kind of quiet that makes it easier to read a landscape slowly. The upright slabs at the mound's western edge are the most visible feature from ground level, and the eroding face where the midden material occasionally shows is worth examining closely if conditions allow, though the exposure shifts with weather and season.