Its full extent has never been properly measured, and it sits as one of three such sites clustered along the same watercourse, which tells you something about how deliberately this landscape was once used.

What lies here is a fulacht fia, a type of site found in considerable numbers across Ireland, typically dating to the Bronze Age. The basic principle involves a trough sunk into the ground, filled with water, and heated by dropping fire-cracked stones into it. Those stones, once spent, were piled to the side, forming the characteristic horseshoe-shaped mound of shattered, darkened rock that survives at so many sites. The proximity to water was essential, and the marshy ground beside a stream was, counterintuitively, ideal territory. Archaeologists have debated for decades what fulachta fiadh were actually used for: cooking is the traditional answer, but brewing, hide-working, and bathing have all been seriously proposed. The three examples at Aglish, lined up along the same northern bank, suggest repeated, deliberate activity at a place people returned to over time, though whether all three were in use simultaneously or represent different phases of occupation remains unknown.