A fulacht fia, the remains of a prehistoric cooking site, once stood here as a low mound of burnt stone and charred earth. These features, found in their thousands across Ireland, were typically used during the Bronze Age: a trough would be filled with water, stones heated in a nearby fire and dropped in to bring the water to a boil, and meat cooked in the resulting heat. The scattered, fire-cracked stone that accumulates from this process gives fulachta fia their characteristic appearance, and their characteristic smell when freshly excavated, of old burning. At Knockognoe, that mound is gone.

When the Castleisland District Archaeological Survey recorded the site in 1985, the levelling had already happened, carried out during the 1980s. What the survey found were the traces left behind after the mound was cleared: burnt soil and the reddened, shattered stone still visible in the disturbed ground. The landowner, speaking to the surveyors, recalled that the original mound had been horseshoe-shaped, with the open end of the curve facing northeast. That horseshoe form is one of the more recognisable shapes a fulacht fia can take, the hollow at the centre corresponding to where the cooking trough would have sat. The recorded dimensions of the site, eleven metres northeast to southwest and just under seven metres northwest to southeast, give some sense of the scale of what was lost, a modest but meaningful presence in the landscape before it was flattened.