The newer of the two, a horseshoe-shaped mound measuring roughly five metres across and just thirty centimetres high, has been built onto the western edge of an earlier site, as though whoever chose the spot was drawn to a place already marked by use.

Fulachta fia are among the most common prehistoric monument types in Ireland, low, often crescent-shaped mounds formed from heat-shattered stone and charcoal, the debris left behind when stones were repeatedly heated and plunged into water-filled troughs to bring them to the boil. The process was repeated over many sessions, cracking the stones each time, and the discarded rubble gradually built up into the characteristic mound. The Rathlogan example sits north of a meandering stream in the floodplain of a small east-west valley, a location entirely typical of the type. Access to running water was essential, and Bronze Age communities returned to the same favourable spots again and again. That pattern is plainly visible here: this site is one of a cluster of at least three fulachta fia positioned close together along the same stream. The small depression recorded on the mound surface, around a metre in length and only twenty centimetres deep, may mark where a trough once sat.

What makes the site quietly interesting is less any single feature than the accumulated layering of it. The superimposition of one fulacht on another, and the clustering of several such sites in the same narrow valley, suggests this stretch of water was a focal point for repeated activity across generations, or possibly centuries, of prehistoric use.