Visible as a thin band of compacted shell just beneath the surface of a vertical scarp above the foreshore, a kitchen midden stretches for roughly thirty metres along the cliff edge. A midden, in archaeological terms, is simply a refuse heap left by past inhabitants, the accumulated debris of meals, work, and daily life. This one sits only a metre or so above the shoreline, close enough to the water that you can almost reconstruct the logic of it: shellfish gathered from the foreshore below, the edible parts consumed, the shells discarded at the edge of the scarp above.

The deposit runs between ten and thirty centimetres thick and lies just a centimetre or two below the sod, which means it is both shallow and remarkably legible. The material is predominantly oyster shells, with some limpets also present. The island's name is not incidental here; oysters were clearly a significant resource in this place. The site was already considered noteworthy enough to be marked on the Ordnance Survey six-inch map of 1940 to 1941, where it appears under the label 'Kitchen Midden', a term that was in common use by that period as archaeologists and surveyors began recognising such deposits as meaningful traces of human activity rather than simply old rubbish. Exactly when the midden was formed, and by whom, is not recorded, though shell middens in Ireland range in date from prehistoric periods through to early modern times, and their proximity to tidal resources is a consistent feature across that entire span.