It is, in fact, the remains of a fulacht fia, one of the most widespread and quietly puzzling monument types in the Irish archaeological landscape. These are the remnants of ancient cooking sites, typically Bronze Age in origin, where stones were heated in fire and then plunged into a water-filled trough to bring it to the boil. The process left behind a characteristic horseshoe-shaped mound of shattered, fire-cracked stone, and it is this accumulated debris that survives at Knockshanawee as a slight rise in marshy terrain.

The site was recorded as a mound on the Ordnance Survey six-inch map of 1943, which gives some sense of how long it has sat in the documentary record without attracting much further attention. Its location in wet, low-lying ground beside a watercourse is entirely typical of the fulacht fia tradition; ready access to water was a practical necessity for the process, and such sites cluster predictably along stream margins and in damp hollows across Ireland. The marshy setting that made the site useful in prehistory is also, in part, what has preserved it, keeping the mound undisturbed beneath layers of encroaching vegetation.

The mound is not accessible, and can only be viewed from a distance. In that sense it belongs to a category of sites that repay knowing about more than they reward visiting, places where the interest lies in what the landscape is quietly holding rather than in anything a visitor can directly examine.