What makes the site quietly remarkable is not its visibility, which is essentially nil, but what erosion and excavation have together pulled from it: a layered record of people living, eating, and farming on this Atlantic edge between roughly 430 and 680 AD.

The site first came to scholarly attention when antiquarian T. J. Westropp noted hearths and burnt stones eroding from the dunes in 1914. It was not until 1992, following further severe erosion, that a formal excavation was carried out by Zajac. The dig revealed two distinct occupation layers. The lower level, about half a metre deep, consisted of yellow sand flecked with charcoal and burnt bone, and built up gradually over time through weathering and trampling. The bones recovered were those of cattle, sheep, pig, and horse, along with fragments of cut red deer antler, and hearths to the south-west of the layer contained charred oats, barley, and wheat. Curiously, there was a complete absence of fish bones or shellfish at this level, suggesting a diet focused firmly on farming rather than the sea, despite the coastal setting. The upper layer told a different story. Darker, charcoal-enriched, and roughly forty centimetres deep, it contained bones of cod, hake, and wrasse alongside shells of periwinkle, limpet, cockle, scallop, mussel, and oyster, as well as a single puffin bone and a clay brooch mould, the latter being a small fired-clay form used to cast metal dress fasteners. Radiocarbon dating of animal bone placed the lower level at around 1513 BP and the upper at 1382 BP, confirming continuous activity across approximately two and a half centuries. At some later point, the site was reused as a burial ground, and graves were dug down through the upper occupation layer, disturbing it considerably.

The occupation layers were found to extend beyond the limits of the 1992 excavation, meaning the full spread of the settlement beneath the dunes remains uncharted. Poll An Chapaill, the name of the inlet, translates roughly as the hole or inlet of the horse, and the dunes above it still hold whatever else those early medieval inhabitants left behind.