A fulacht fia, to give the type its Irish name, is essentially an outdoor cooking place, typically Bronze Age in character, where water was heated by dropping fire-cracked stones into a trough or pit. The stones shatter with repeated heating and cooling, and it is that dense scatter of burnt, fragmented rock that archaeologists recognise as the signature of the site. At Castlemungret in County Limerick, one such feature lay entirely concealed beneath natural grey sediment until a gas pipeline brought it to light.

The site was identified by archaeologist Ken Wiggins in 2002 during monitoring work along the Bord Gáis Éireann Barnakyle to Coonagh West pipeline, and was subsequently excavated under licence by Wiggins the same year. What had initially appeared as a roughly circular spread of charcoal-rich clay, about 4.5 metres in diameter, turned out on full excavation to measure 8.5 metres north to south and 5.5 metres east to west, with the burnt stone layer running up to 0.25 metres thick. Beneath the spread, cut directly into the boulder clay, was a curving channel measuring 2.7 metres in length and up to half a metre deep on its western side; this is likely to have functioned as the water trough central to the site's use. A pit-like feature near the western edge contained sandstone blocks alongside burnt stone and charcoal in its lower fill, and ash and darker silty clay above. A stone culvert aligned roughly south-west to north-east was also recorded at the north-western corner of the site, and a linear cut ran close to the northern edge of the burnt spread. An enclosure of separate record lies approximately 26 metres to the south-west.

The site was excavated ahead of pipeline construction and no visible trace is likely to remain at ground level today. Its interest lies less in what can be seen now than in what the excavation revealed: a well-used, carefully structured prehistoric cooking place whose full extent had been entirely masked by later sediment accumulation. Anyone with a serious interest in the archaeology of this part of Limerick would do well to consult the excavation summary published on excavations.ie under the 2002 entry, reference number 1143, which sets out the stratigraphic detail in full.