Middens, as such refuse heaps are known, are among the most informative features an archaeologist can find. The mundane nature of a midden is precisely the point; it is a record of daily life rather than ceremony or defence, and this one, lying to the south of a prehistoric house, speaks quietly but precisely about who sheltered here and how they got by.

The deposit was examined during research excavations at Dún Aonghasa and contained far more than shellfish remains. Among the finds were fragments of pottery, pieces of pumice, bone points, a bone pin, coarse stone tools, a bronze ring, and a heavily corroded broken bronze implement. Pumice, carried to the Atlantic coast on ocean currents from volcanic regions far to the north, turns up fairly regularly on Irish prehistoric sites and was used for smoothing and abrading. The presence of bronze objects, even fragmentary and corroded ones, places the site within a metalworking culture of some sophistication. Four flat stones projecting from beneath the foundation course of the inner enclosure wall to the south appear to have marked the end of the midden's use, and animal bone recovered from those stones was radiocarbon dated to between 900 and 510 cal. BC, placing the close of this particular occupation sequence firmly in the Late Bronze Age.