It measures roughly 60 metres by 35 metres, its shape described in the archaeological record as subrectangular, meaning it follows a broadly rectangular outline but without the regularity you would expect from a planned medieval or post-medieval feature. That subtle irregularity is, in itself, a clue worth pausing over.

The enclosure was not spotted by anyone walking the fields but was identified through aerial photography, as part of the Bruff Survey, a systematic effort to record archaeological features across this part of Limerick. It appears in that survey as Map 33, Bruff 126, with the reference 4/3615. The record draws on work by Doody, published in 2008, who noted that the enclosure's morphology, its overall shape and form, suggests a possible Bronze Age date. The Bronze Age in Ireland spans roughly 2500 to 500 BC, a period when communities built enclosures for a range of purposes: settlement, ceremonial use, or the enclosure of livestock and agricultural land. No excavation is recorded in the available notes, so the date remains a suggestion based on form rather than confirmed finds.

Because the enclosure was identified from the air rather than from ground survey, it may be barely legible at field level, surviving as a slight earthwork or as a cropmark, a patterning in growing vegetation that reveals buried features to cameras but not always to the naked eye. Visitors to the Ballynagreanagh area should be aware that access to field monuments in private farmland requires the landowner's permission, and that features of this kind can be frustratingly elusive underfoot. The broader landscape around Bruff rewards careful attention, sitting within a part of Limerick that has been settled and farmed for millennia, and the aerial survey that caught this enclosure has catalogued many such traces across the region.