It measures roughly nine metres north to south, five metres east to west, and rises less than a metre from the ground. Partially obscured by encroaching bushes and trees, it is the kind of feature that most walkers would step around without a second thought, mistaking it for a natural rise in the boggy ground.

What they would be stepping past is a burnt mound, one of the most common yet least understood monument types in the Irish archaeological landscape. These features, sometimes called fulacht fiadh in the Irish tradition, are typically interpreted as the remains of ancient cooking or heating sites, where stones were heated in fire and then plunged into a water-filled trough to bring it to the boil. The repeated cracking of the stones under thermal stress, and their subsequent dumping, produced the characteristic horseshoe or kidney-shaped mounds of shattered rock and ash that survive across Ireland in their thousands. The Glanareagh example dates, in recorded form at least, to a survey reference from 1998, though the activity it represents almost certainly belongs to the Bronze Age, when fulacht fiadh use was at its peak. What makes this particular spot quietly notable is that it does not stand alone: a second burnt mound lies approximately twelve metres to the north, suggesting repeated or prolonged activity at this streamside location, with its reliable water source making the spot well suited to whatever process was being carried out. The stream that once served those purposes is now gradually undoing the mound itself, eroding its eastern edge as it goes.