It was only the infrastructure demands of the Limerick Main Drainage Scheme that prompted the archaeological monitoring which brought it to light, and what emerged was a fulacht fia, one of Ireland's most common yet still not fully understood prehistoric monument types. These sites, found in their thousands across the island, are generally interpreted as outdoor cooking places, where stones were heated in fire and then dropped into water-filled troughs to bring the liquid to a boil. The broken, fire-cracked stones, discarded after repeated use, gradually built up into the characteristic mounded shape that survives in the landscape today.

Excavation was carried out by Edmond O'Donovan under licence number 00E0431, and the results revealed a site of considerable complexity. The mound itself measured roughly 13 metres north to south by 14 metres, with a burning area filling the open western end of the horseshoe. Beneath the mound material, excavators uncovered two principal troughs. Trough C17 was sub-oval in plan and notable for a subcircular arrangement of stake-holes cut into its sand-lined base, suggesting a timber structure of some kind, possibly a lining or frame to hold the trough together. Trough C18 was more regularly shaped, with near-vertical sides and evidence of plank settings in its flat base, indicating a lined, water-tight wooden vessel. A third trough feature was also identified, though it either pre-dated the main monument or was never finished. In total, 80 features were recorded across the site, including 58 stake-holes, 5 plank settings, and various pits. Two artefacts were recovered, a flint flake and a chert hollow-based arrowhead, the latter pointing towards a Late Neolithic or Early Bronze Age origin. Radiocarbon dating of charcoal from the lower trough fill subsequently confirmed activity at the site between approximately 2199 and 1983 BC. Roughly 15 metres to the north, a separate feature was found, a V-shaped pit nearly three-quarters of a metre deep, associated with a band of charcoal-rich clay extending about 7 metres east to west, which had left no surface trace whatsoever before excavation began.

The site at Rathbane South is not accessible as a visitor destination; it was uncovered during construction works and is not preserved in situ in any publicly visible form. Its significance lies instead in the record it produced. For anyone interested in following up, the excavation summary is available through the Irish Archaeological Excavations Database, reference 0607, and O'Donovan's published findings offer further detail on the radiocarbon dating and phasing of the monument. The broader landscape around south Limerick has seen considerable development-led archaeology over the years, and the county's Sites and Monuments Record holds records of comparable features in the region.