Middens are among the most unassuming of archaeological features, essentially ancient rubbish dumps, yet they are frequently the most revealing. Shells, fish bones, animal remains, fragments of pottery, the occasional tool or ornament; all of it compacted over years or centuries into a layered record of daily life that burial mounds and ringforts rarely match for sheer intimacy.

Mayo's coastline has long been associated with shell middens in particular, where communities exploiting the rich intertidal and nearshore environments left accumulations of oyster, limpet, and periwinkle shells that can survive for thousands of years under the right conditions. Some Irish middens date to the Mesolithic period, when small groups of hunter-gatherers moved along the western seaboard, while others reflect the food practices of later farming communities. Without more specific information available about the Bun An Mhuilinn example, it is not possible to say with confidence when this particular deposit was formed or by whom, but its recorded existence as a monument indicates it was considered significant enough to warrant formal recognition.

The place name itself offers a quiet clue to the longer human presence in this corner of Mayo. Mills require not just water but settled communities, grain cultivation, and a degree of local organisation, suggesting that Bun An Mhuilinn was a place of some activity long after whoever left the midden had gone. The two features, the ancient deposit and the later mill, now exist only as traces, one in the ground and one in the name of the place.