This enclosure in the townland of Cross, within the barony of Coonagh in County Limerick, is one of them. It has never appeared on Ordnance Survey historic mapping, cannot be made out on satellite imagery taken in 2011, 2012, 2013, or 2018, and the cropmark evidence that first brought it to attention has since been judged unconvincing. And yet it sits in the record, noted and numbered, waiting for a clearer answer.

The site was first identified during the Bruff aerial photographic survey in 1986, when a flyover produced an image, catalogued as Bruff 107 (AP4/3676), appearing to show a large, roughly sub-circular area enclosed by a fosse, that is, a defensive or boundary ditch, with the Reask River intersecting it at its northern edge. The Reask River is not incidental here; it marks the townland boundary between Cross and Brackyle, which places this putative enclosure right at the edge of one territorial unit and the beginning of another, a location that, in other contexts, would be entirely consistent with early medieval enclosures used for settlement or ritual purposes. The surrounding landscape adds some weight to the mystery: a cluster of five ring-barrows, the low circular earthen mounds typically associated with Bronze Age burial, lies roughly 70 metres to the southwest, and a further cluster of barrows along with additional earthworks sits around 150 metres to the southeast. Whether or not the enclosure itself proves to be real, it sits amid genuine and documented archaeology.

For anyone inclined to visit, the site lies in pasture immediately south of the Reask River, roughly 218 metres northeast of the townland boundary with Knockballyfookeen. As the monument does not register on recent satellite imagery and shows no surface features visible to the naked eye, there is very little to observe on the ground. Access to any surrounding farmland would require the landowner's permission. The real interest here is less in what can be seen and more in what the 1986 aerial photograph seemed, briefly, to suggest: that somewhere beneath this unremarkable stretch of Limerick pasture, a large enclosed space once held something worth surrounding with a ditch.