It measures roughly eight metres long, eleven metres wide, and less than a metre high, its opening facing south. Without knowing what to look for, you could walk past it without a second thought. But this modest rise in the earth is a fulacht fia, a type of prehistoric cooking site found in enormous numbers across Ireland, and this one is not alone.

Fullachta fiadh, the plural form, are among the most commonly recorded archaeological monuments in Ireland. The basic principle involved digging a trough near a water source, lining it to hold liquid, and heating stones in a fire before dropping them into the water to bring it to a boil. The shattered, fire-cracked stones were then discarded to the sides, accumulating over repeated use into the characteristic horseshoe or kidney-shaped mounds that survive today. They are most often found in low-lying, wet ground, which is precisely the setting here at Glynn. What makes this particular site quietly remarkable is its company: it belongs to a cluster of four fulachta fiadh in close proximity, with another sitting immediately to the northwest. Whether they were used simultaneously, or represent different episodes of activity across many generations, is difficult to say, but their concentration in one stretch of boggy ground suggests the area was returned to repeatedly, perhaps because of a reliable water source or some other feature that no longer survives in the visible record.