It measures 18.7 metres east to west and 15.5 metres north to south, rising to a height of 2.1 metres, with a two-metre opening facing north. Two linear arms extend outward, one running roughly eight metres to the south, another about 9.4 metres to the southwest, giving the whole feature an unusually elongated footprint. A cluster of four small mounds, each about two metres across, sits just north of the opening.

This is a fulacht fia, a type of prehistoric cooking site found in enormous numbers across Ireland, particularly in low-lying or waterlogged ground. The characteristic form is the burnt mound itself, a crescent or horseshoe of fire-cracked stone and charcoal that accumulated as heated rocks were used to boil water in a nearby trough, then discarded when they shattered. The process was repeated over time, sometimes over many generations, and the mounds grew accordingly. The example at Cloghvoula is notably substantial, and the presence of the extending arms and the small satellite mounds to the north suggests a more complex arrangement than a simple cooking pit. Whether those features represent different phases of use, ancillary activities, or something else entirely is the kind of question that only excavation tends to settle.