A decade earlier it had been something more legible: a compact, grass-covered horseshoe-shaped mound roughly nine metres east to west and twelve metres north to south, rising about three quarters of a metre above the surrounding pastureland. That horseshoe form is characteristic of a fulacht fia, a type of site found in considerable numbers across Ireland and generally associated with Bronze Age cooking. The method involved heating stones in a fire, dropping them into a water-filled trough to bring it to a boil, and repeating the process until whatever was being cooked was done. The discarded, fire-cracked stones accumulated over time into the distinctive curved mound that survives at so many sites. Here, that mound no longer stands.

The site came to light in 2002 during field walking carried out alongside the Lough Mask Regional Water Supply Scheme, a infrastructure project running between 2001 and 2002. Field walking, in archaeological terms, involves systematically crossing a stretch of ground on foot to record surface finds and features before or during development work, and it was this methodical approach that caught the fulacht fia before any formal record could be made of it in three dimensions. The mound sat on the northern bank of a stream or drain, in reclaimed pastureland, the kind of low-lying, wet ground where fulachta fia are commonly encountered, since proximity to water was essential to the whole process. When researchers returned in 2012, land reclamation works had levelled the mound entirely. What remains visible now is a surface spread of burnt stone and charcoal, its extent suggested more by a change in vegetation cover than by any upstanding feature. A second burnt mound lies approximately 110 metres to the north, hinting that this corner of Treannaskehy was visited repeatedly, or at least that the conditions here suited this kind of activity across some stretch of time.