This is a fulacht fia, a type of prehistoric cooking site found in great numbers across Ireland, typically consisting of a trough that would have been filled with water and heated by dropping fire-cracked stones into it. The cracked and blackened stones, discarded after use, gradually accumulated into a low mound. What survives at Aglish is a spread of that same burnt material, its full extent as yet unmeasured.

What makes this particular spot a little more interesting is that it does not sit alone. A second fulacht fia lies roughly fifteen metres to the west, making this a paired site. Such clustering is not unheard of; fulachtaí fia are sometimes found in loose groupings near water sources, though whether paired examples represent simultaneous use, repeated return to a favoured spot over generations, or something more organised is rarely easy to determine from surface evidence alone. Both sites lie in open pasture, where centuries of grazing and seasonal ground movement have done their quiet work on whatever archaeology remains beneath.