What looks like discarded domestic waste, principally the shells of oysters, mussels, limpets, and other shellfish, accumulated over generations of coastal living, turns out to be one of the more reliable records of early human settlement. Middens preserve not just shells but animal bones, charcoal, pottery fragments, and occasionally human remains, building up in stratified layers that can be read almost like the pages of a book. The presence of one at Ballincar places this quiet stretch of Sligo coastline within a pattern of prehistoric occupation found all along Ireland's western seaboard, where communities lived in close relationship with the sea over thousands of years.

Ballincar sits on the southern shore of Sligo Bay, a landscape shaped by the same glacial activity that deposited the distinctive drumlins and raised beaches found throughout the region. Coastal middens in Ireland date from the Mesolithic period onwards, some going back more than nine thousand years, though without more detailed records it is not possible to say precisely when this particular accumulation began or how long it was in use. What is certain is that whoever left it behind was making sustained use of the shoreline, returning repeatedly to harvest shellfish and process other food, in the way that coastal communities did long before farming became the dominant way of life.