This one in Treanacally, County Mayo, is perhaps more remarkable for what it no longer does. Recorded on official registers as a fulacht fia, a type of prehistoric cooking site typically identified by a horseshoe-shaped mound of fire-cracked stone left behind after repeated cycles of heating rocks and dropping them into a water-filled trough, the site now shows no trace of that origin at ground level. The mound, if it ever formed one, is simply gone.

The site sits on a narrow strip of level ground between the Mullaghanoe River to the east and rising land to the west, a position that fits the pattern well. Fulachtaí fia are almost always found near water, which was essential to their function, and low-lying ground beside rivers or streams is exactly where they tend to cluster across the Irish landscape. It was listed as a fulacht fia in the Sites and Monuments Record in 1991 and again in the Record of Monuments and Places in 1997, both times on the basis of local information rather than physical survey. When the location was inspected in 1996, no archaeological evidence was visible at ground level. Land reclamation had taken place in the area, and spoil had been spread across the surface. The working conclusion was that the monument had been levelled in the process.