It is a fulacht fia, a type of prehistoric cooking site found in considerable numbers across Ireland, and it is easy to miss entirely. These sites typically consist of a horseshoe-shaped mound of fire-cracked stones, the discarded debris from repeated cycles of heating stones and dropping them into water-filled troughs to cook meat or process other materials. Most date to the Bronze Age, roughly 1500 to 500 BC, though some were in use earlier or later. What makes this one quietly arresting is not any grand visible feature but the opposite: it endures as an unquantified heap, its dimensions still undetermined, pressing up through scrub and vegetation within roughly six metres of a local well.

The proximity to water is entirely typical. Fulachtaí fia, to use the Irish plural, are almost always found near a reliable water source, whether a stream, a spring, or a well, since water was the operational heart of the process. The well near this site at Mashanaglass may itself be ancient, though nothing in the available record connects the two with certainty. What can be said is that someone, at some point in prehistory, returned to this spot often enough to build up a substantial mound of heat-shattered stone, each fragment cracked and blackened by thermal shock. The burnt material in such mounds accumulates over many uses; a heavily overgrown mound like this one suggests considerable volume beneath the vegetation, even if no formal excavation has established its extent.