What the Ordnance Survey cartographers of 1842 marked as "Knockadoony Fort" is, by any honest measure, a modest thing: a subcircular enclosure barely fifteen metres across at its widest, its defining bank worn in places to little more than a scarp, and broken at several points by livestock gaps knocked through over generations of farming. The name "fort" carries a certain weight, but the structure is formally classified as an enclosure, a category that covers a wide range of prehistoric and early medieval earthworks whose original purpose, whether domestic, ritual, or defensive, is rarely settled by the earthwork alone.

The site appears on both the first edition Ordnance Survey six-inch map of 1842 and the later Cassini edition of 1920, meaning it was recognised and recorded across nearly a century of mapping, even as the bank itself was quietly diminishing. The enclosing bank averages about 1.2 metres in width, standing only around 0.1 metres above the interior ground level but roughly 0.7 metres above the exterior, giving it a more pronounced outward face. That asymmetry is typical of earthen enclosures where material was piled inward from a surrounding ditch. A possible outer fosse, a shallow ditch running along the north-east to south-east arc, is faintly visible, though at a depth of around 0.1 metres it survives only as a suggestion. Curiously, the interior rises slightly toward the centre, sitting a little higher than the ground immediately inside the bank, a detail that can sometimes indicate accumulated occupation material beneath.

The location offers wide views northward and southward along the hillside, and it is this quality of prospect that perhaps explains the choice of site as much as anything else. Whatever gathered here, and whenever, it commanded attention across the surrounding landscape even if the landscape has since largely forgotten it.