This was a fulacht fia, a type of Bronze Age cooking site found in their thousands throughout Ireland, typically identified by exactly this signature: a spread of heat-shattered stone accumulated over repeated use, often curving around a timber-lined trough into which water was poured and heated by dropping in fire-hot stones. The site at Kellymount would almost certainly have remained buried and unrecorded had a major road scheme not passed directly over it.

Excavation in 2007, carried out ahead of the N9/N10 Kilcullen to Waterford road improvement scheme, revealed a spread of burnt material measuring sixteen metres by fifteen metres and around forty centimetres deep. Beneath it lay a sub-rectangular trough with stake-holes at each corner, radiocarbon dated to between approximately 2133 and 1940 cal BC, placing it in the Early Bronze Age. A second trough, excavated around eight metres to the west, returned a later date of 1679 to 1523 cal BC, suggesting the site was in use across several centuries and possibly abandoned and reoccupied between episodes. Between the two troughs, excavators uncovered a large pit or waterhole, four metres in diameter and two metres deep, which produced a surprisingly different date: somewhere between cal AD 236 and 380, placing its use in the late Roman period, centuries after the troughs had gone cold. A horseshoe-shaped arc of post and stake-holes enclosed an area roughly six metres by three and a half metres to the north-east of the waterhole, though what activity this structure once sheltered remains unknown. Further pits, post-holes, and stake-hole clusters across the excavated area could not be dated at all, leaving open the question of how many distinct phases of activity the ground here actually holds.