It is horseshoe-shaped, roughly eleven metres across at its widest and just under half a metre tall, with its open, in-curved face turned to the south. To the untrained eye it might read as a natural rise in the ground, a trick of the terrain. It is, in fact, a fulacht fia, a type of prehistoric cooking site found in great numbers across Ireland, and one of the more quietly eloquent survivals of Bronze Age domestic life.

Fulachtaí fia, the plural form, are typically dated to the Bronze Age, though examples span a wide chronological range. They consist of a trough, usually timber-lined or stone-lined, dug near a water source, and a surrounding mound of burnt and shattered stone. The standard interpretation is that stones were heated in a fire and then dropped into water-filled troughs to bring the water to a boil, the cracked and discarded stones accumulating over time into the characteristic horseshoe shape. The open end of the mound generally marks where the trough once sat. Here at Addergown, the geometry fits that pattern precisely: the stream nearby would have supplied the water, and the southward-facing curve of the mound preserves the rough outline of where people once gathered to cook, or possibly to bathe or process materials, debates about the exact function of these sites remain lively among archaeologists. The site was documented as part of the North Kerry Archaeological Survey, published in 1995 by C. Toal.