The Ordnance Survey mapped it in 1840 under the name Ahadoon, rendering the Irish as Áth a' Dúin, meaning ford of the fort. That name points westward, toward the Morningstar River, 125 metres away, where a crossing called Doon Ford was also noted on the same map. The site itself sits beside an old road that once ran between Knocklong and Kilmallock, and the ford, the road, and the earthwork seem to form a cluster of features that once worked together, controlling movement across a boundary. The Morningstar River still marks the townland boundary between Knocktoran and Ballinvana, and the name of the townland itself, Cnoc Teorann, means Hill of the Boundary.

Whether the mound is an early medieval platform ringfort, a type of enclosed homestead typically dating from the sixth to tenth centuries, or a medieval motte castle, a raised earthen mound built by Norman lords as a military base, remains unresolved. The antiquary Thomas Johnson Westropp described it in detail between 1917 and 1919. He measured it at between 4.8 and 5.4 metres high, with a low surrounding ring roughly 2.4 to 3 metres thick and rarely reaching 0.9 metres above the platform surface. The interior platform measured approximately 18.2 metres across, with the full base spanning around 37.5 metres. He noted traces of a fosse, the defensive ditch that would typically encircle such a structure, though these were already too damaged to measure. By 1840 the interior had been planted with trees, and the 1897 Ordnance Survey map shows the earthwork incorporated into later field boundaries, with outbuildings of Knocktoran House pressing in from the east.

The mound is on private farmland and not publicly accessible, but its tree-covered profile is visible on aerial imagery, rising distinctly above the surrounding pasture. The old road that Westropp described as running from the mound down to the ford can still be traced in the landscape. Visitors passing through the area on the road between Knocklong and Kilmallock are, in effect, travelling a route that the 1840 surveyors already regarded as old, and which likely predates any map made of it.