It exists, as far as the record is concerned, almost entirely because a single aerial survey happened to pass over it at the right moment, under the right conditions, nearly forty years ago.

The monument is a ring-barrow, a type of low circular earthwork, typically consisting of a central mound or flat area surrounded by a bank and ditch, associated with burial practices in prehistoric Ireland. It sits in flat pasture roughly 130 metres east of the townland boundary with Ballyshoneen, and it does not stand alone in the landscape. Within a short distance lie a related enclosure to the north-west and a second ring-barrow to the north-north-west, suggesting this corner of south Limerick was once used, over a long period, for commemorating or interring the dead. The Knockballyfookeen barrow was identified in 1986 through the Bruff aerial photographic survey, catalogued as Bruff 91 and recorded under reference AP 4/3672. That survey image remains one of the only direct visual records of the site. Subsequent orthoimages taken between 2005 and 2013 by Ordnance Survey Ireland and Digital Globe, and Google Earth imagery from November 2018, show nothing. The monument has been compiled in the record by Edmond O'Donovan, with the entry uploaded in September 2020.

Because the feature is not marked on historic maps and is invisible under normal photographic conditions, there is little a visitor could reasonably locate without specialist guidance or access to the original survey material. The surrounding land is private agricultural pasture, and the lack of any surface expression means there is nothing obvious to observe even from a field boundary. What makes the site worth knowing about is precisely this quality of near-invisibility: it is a reminder that the archaeological record of even a well-studied county like Limerick is still being assembled, and that some monuments survive not as earthworks but as a single frame of aerial film taken on one particular afternoon in 1986.