What the diggers found was not dramatic in appearance: thin scatters of fire-cracked stone across a roughly twenty-metre square, and a single oval trough sunk into the ground. Yet these modest remains are the signature of a fulacht fia, one of the most widespread and still debated monument types in the Irish archaeological record. A fulacht fia, found in enormous numbers across Ireland, is generally understood to have been a Bronze Age cooking site, where water in a stone-lined trough was heated by dropping fire-heated stones into it; though some archaeologists have proposed other uses, from textile processing to brewing. The trough at Kilfinny, though the surrounding burnt mound had been considerably damaged, survived in reasonable condition.

The site was excavated by Graham Hull in 2002 as part of Bord Gáis Éireann's Pipeline to the West scheme, reference 02E0581. The trough itself was oval, measuring 2.05 metres north-east to south-west by 1.6 metres, bowl-shaped in profile with gently sloping sides reaching a flattish base 0.45 metres deep. Five distinct fills had accumulated inside it over time: a light grey ashy silt at the base, followed by a dark silty clay containing 45 to 55 per cent burnt limestone fragments, then a peaty dark brown-black deposit, a thin later scatter of disturbed burnt stone, and finally topsoil. The layered nature of these fills is precisely what makes such a trough archaeologically useful; the stratified deposits could allow radiocarbon dating to refine the chronology of the site. Three artefacts were recovered nearby: two flint flakes from the disturbed burnt stone deposits, and a piece of bottle glass from the uppermost fill. The flint flakes, though modest finds, contribute to the small body of artefactual material known from fulachta fiadh more generally. The stream immediately to the south-east of the site had at some point cut through the burnt stone deposits, and modern agricultural activity had likely done further damage to what may once have been a more substantial mound.

There is nothing to see at this location today. The site was identified and recorded during topsoil-stripping for pipeline construction, and the process of that same work probably caused significant damage to the burnt mound before excavation could take place. Its interest lies entirely in the record rather than the ground. For those curious about fulachta fiadh as a monument class, the excavations.ie database holds the full site report, and the broader Limerick landscape contains many comparable sites, most equally invisible above ground but occasionally surfacing when the land is disturbed.