What makes it quietly puzzling is precisely that ambiguity: the drystone walls look much like any other field boundary in the area, yet the shape they describe, that irregular D with an undulating, kinked curve rather than a smooth arc, suggests something older may lie beneath or behind them.

The enclosure measures approximately 26 metres north-northeast to south-southwest and 34.6 metres west-northwest to east-southeast, with walls between one and 1.4 metres wide. The curving section runs from northwest to northeast, while straight walls close off the eastern, southern, and western sides. There are two breaks in the circuit, one nearly 2.2 metres wide at the east-southeast and a narrower gap of 0.7 metres toward the west. The interior slopes gently downward to the north, its surface uneven and scattered with sod-covered boulders, and a large heap of field clearance stones has been piled against the exterior at the northeast. The enclosure does not appear on the Ordnance Survey six-inch map of 1838, but is clearly shown on the 1920 edition, incorporated into the southern end of a rectangular field. That gap in the cartographic record does not resolve anything; the nineteenth-century walls may simply have been rebuilt over or around a much earlier subcircular or oval enclosure, the kind of ringfort-like structure, a drystone enclosure used historically for settlement or livestock, that is common across the west of Ireland. A second enclosure of uncertain date lies roughly 125 metres to the southwest, which at minimum suggests this corner of Cashelduff was once used in some deliberate, organised way. Whether that organisation was early medieval, early modern, or something in between remains an open question.