A rath is an earthen ringfort, typically a raised circular bank enclosing a farmstead or homestead, built throughout Ireland from the Iron Age into the early medieval period. This one sits on an east-facing slope of Inishfale Island, a roughly circular island measuring about 300 metres across, and its own outer diameter runs to approximately 35 metres. The woodland that now covers the island has swallowed it entirely; at ground level, there is nothing to see.

The clearest record of the feature comes from the 1837 edition of the Ordnance Survey six-inch map, where it appears as a faint circular embanked outline. The OS six-inch series, produced in Ireland during the 1830s, was among the most detailed topographic mapping of its time, and surveyors occasionally captured earthworks that have since been obscured by vegetation or erosion. In this case, the map preserves evidence of a structure that the intervening growth of deciduous woodland has rendered effectively invisible to anyone standing among the trees.