That scarp, roughly half a metre high and eighty metres long, is the feature that draws attention. It may be the eroded remnant of a bank or wall, the kind of barrier that would once have defined a coastal promontory fort, a defensive enclosure that used the natural drama of a headland, with sea cliffs or rocks on its exposed sides, and an earthwork or stone barrier closing off the landward approach. Here, the sea rocks lie to the south and a deep chasm drops away to the north, leaving only this narrow neck as a point of entry or attack. The interior of the headland is featureless and scattered with loose rock, and about ten metres to the east there stands a cairn of stones whose relationship to any fortification, if one ever existed here, is unclear.

The site appears on Ordnance Survey maps marked with a line of hachuring across the neck of the headland, the conventional symbol for an earthwork, but it carries no name. That anonymity is part of what makes it interesting. Markus Casey, in a 1999 unpublished MA thesis surveying the coastal promontory forts of counties Sligo, Mayo, Galway, and Clare, catalogued this location as a possible site, which means the evidence is suggestive rather than conclusive. The scarp could be a natural geological feature rather than a constructed one. Inishkea South, one of two Inishkea islands lying off the Mullet Peninsula, was inhabited until 1934, and the landscape carries traces of many periods of human activity, which complicates the reading of any single feature in isolation.