A shell midden is essentially a compressed deposit of food waste, the accumulated discards of people who gathered shellfish and ate them where they stood or nearby. This particular midden, sitting roughly 26 metres west of Doonmore castle, is notable for a quiet internal logic: the western end is composed almost exclusively of limpet shells, while the eastern end shifts to dog whelks, suggesting either different periods of use, different gathering habits, or both. It measures 3.3 metres in length and survives to nearly 60 centimetres below the present surface. Immediately to its west, a second, lighter scatter of dog whelks is also exposed, and two further middens lie just 6 and 13 metres to the east, making this a small but dense cluster of coastal refuse that accumulated over time.

The site sits within a broader landscape that has attracted archaeological attention for some years. Banks in an adjacent field were identified as a possible promontory fort as early as 1999 by Casey, and a later study by Coyne, Darmody, and O'Mahony in 2008, carried out ahead of proposed development at Doonbeg pier, reconsidered those same banks as a possible bawn, a walled enclosure typically associated with a tower house or castle, in this case relating to nearby Doonmore castle. The middens themselves were formally recorded during that same 2008 survey. Reports prepared in 2014 and 2015 suggested the deposits had been newly exposed by severe storm activity, meaning the sea that once supplied the shellfish was now, centuries later, gradually uncovering the evidence of their consumption.