The site at Killoran is a fulacht fia, a type of ancient cooking place found in enormous numbers across Ireland, typically identified by a horseshoe-shaped mound of fire-cracked stone and charcoal left over from repeated use. The principle was straightforward: heat stones in a fire, drop them into a water-filled trough, and bring the water to a boil without any direct flame. What makes Killoran quietly remarkable is that the trough was not filled by hand or by rain but by a natural spring rising directly beneath it, suggesting whoever chose this spot did so deliberately, selecting a place where the ground itself would do part of the work.

Excavation of the site revealed a subcircular trough measuring roughly 1.5 metres across and 0.4 metres deep, surrounded by a semicircular spread of burnt material spanning approximately 7.5 metres in diameter. A separate concentration of charcoal-rich clay to the south-east of the trough is thought to represent the hearth where stones were heated before being transferred to the water. Radiocarbon dating of the charcoal placed activity at the site between approximately 2138 and 1935 BC, placing it firmly in the Early Bronze Age. The site sits on poorly drained ground, the kind of wet, low-lying terrain where fulachta fiadh are most commonly found across the Irish landscape, and where a subsurface spring would have been a reliable and valued resource.