It measures eighteen metres at its longest and rises to about 1.3 metres, and it is composed almost entirely of burnt and heat-shattered stone. This is a fulacht fia, a type of prehistoric cooking site found in considerable numbers across Ireland. The working theory is that stones were heated in a fire, then dropped into a water-filled trough to bring it to a boil, producing heat that could be used for cooking or, possibly, bathing and textile production. The burnt, cracked stones were then discarded into a characteristic horseshoe-shaped or oval mound, which is precisely what survives here.

The site sits on the eastern side of a field drain, immediately adjacent to a spring, which is entirely typical of the type. Fulachtaí fia are almost invariably found near reliable water sources, and the spring here would have made this spot consistently practical across many seasons of use. The burnt material is not just confined to the visible mound; it can be seen exposed in the field fence that runs parallel to the drain, suggesting the mound extends or has been partially disturbed by the fence line over time. What makes Gortnascregga quietly notable is that it is not alone. A second fulacht fia lies roughly a hundred metres to the north-west, which points to this particular corner of North Cork having been a repeatedly used or perhaps even valued location in prehistory. Whether the two sites were in use simultaneously or represent separate episodes of activity centuries apart is impossible to say without excavation, but their proximity is suggestive of a landscape that people returned to.