It measures about eight metres across and rises just over a metre in height, its edges held in place by a stone revetment, a facing of stones used to retain the earthen material. To a casual eye it might pass for a natural rise in the landscape. In fact it is a fulacht fia, a type of prehistoric cooking site found in considerable numbers across Ireland, and this one preserves the characteristic dark, crumbly fill that gives these monuments their distinctive appearance: layer upon layer of fire-cracked stone.

Fulachtaí fia, as they are known in the plural, were typically used by heating stones in a fire and then dropping them into a water-filled trough to bring the water rapidly to the boil. The shattered, heat-spent stones were raked out and discarded, and over generations this waste accumulated into the horseshoe or circular mounds that survive today. They date most commonly to the Bronze Age, roughly 1500 to 500 BC, though some examples fall outside that range. The marshy, streamside location at Oughtihery is entirely typical. These sites almost always appear near water, both because a reliable water source was essential to the process and because low-lying, wet ground was less likely to be disturbed by later agriculture. The stone revetment here suggests a degree of deliberate construction around the mound itself, which may indicate repeated or sustained use of the site.