This one in Baurnagurrahy, on the eastern bank of the River Aherlow in County Limerick, does not even appear on the historic Ordnance Survey Ireland maps. What is visible on the ground amounts to a roughly circular depression, around 25 metres in diameter, sitting quietly in pasture. Whether it represents the remnant of a prehistoric or early medieval enclosure, or simply a hole dug by someone in the last few centuries, remains genuinely unresolved.

The feature was first formally noted not through a ground survey but through aerial photographs taken on 3 November 1984 as part of the Bórd Gáis Éireann Curraleigh West-Limerick gas pipeline project. Reviewing the strip maps produced from that survey, the site was logged as a possible enclosure, catalogued as Strip Map 3, site 3/1. Circular earthworks of this kind, when genuine, are typically associated with ringforts or enclosed farmsteads of the early medieval period, a type of monument extremely common across the Irish landscape. The difficulty here is that the feature was not recorded on any of the earlier Ordnance Survey mapping, which surveyed Ireland with considerable thoroughness from the nineteenth century onwards. Its absence from those maps raises the possibility that what looks like an ancient enclosure from the air is actually the result of post-1700 quarrying activity, where the removal of stone or gravel over time has left a sunken, roughly circular scar in the ground. The record, compiled by Martin Fitzpatrick and uploaded in November 2021, is candid about this uncertainty, describing the antiquity of the earthwork as doubtful.

The depression remains visible on Google Earth imagery dated 14 September 2019, which is currently the most practical way to examine it before making any effort to visit. The site sits in agricultural pasture, so access would require permission from the landowner. On the ground, the feature would likely read as a shallow hollow rather than anything dramatically defined, and without the overhead perspective that aerial photography provides, it is easy to understand why it escaped earlier notice entirely. For anyone interested in the methodology of landscape archaeology, or in the particular category of sites that resist easy classification, that ambiguity is rather the point.