When archaeologists dug into the southeast quadrant of the site in 1995, they found that people had been living on this ground before anyone thought to encircle it with walls. The hillfort, one of the largest Iron Age enclosures in Ireland, was not the beginning of the story here. Something older was underneath.

The excavation, carried out under the North Munster Project of the Discovery Programme, uncovered the remains of an oval, double-walled structure defined not by stone or timber beams but by 34 stake-holes, the small cylindrical voids left in the earth where wooden posts once stood. The structure measured roughly four metres in external diameter, with an interior space of 2.5 by 3.5 metres, modest enough to suggest a single domestic dwelling. What gave the find particular significance was a layer of occupation debris, the accumulated residue of daily life, found directly associated with those stake-holes and running on beneath the rampart above. The rampart, in other words, had been built over the remains of this earlier habitation. The hut belonged to the first phase of settlement in this part of the site, and when the hillfort was later constructed, its builders raised the middle rampart directly across the spot where people had already been living. A later structure, known from the record as structure D, occupied the same location at a higher level, suggesting the ground here was returned to repeatedly across time.

Mooghaun hillfort sits above Lough Donnell in south County Clare and is considered one of the most substantial later Bronze Age enclosures in western Europe, comprising multiple concentric stone ramparts enclosing a considerable area of hillside. The hut site excavated in 1995 is not visible to the casual visitor, having been recorded and then left beneath the landscape, but its presence complicates any simple reading of the hillfort as a single, planned construction. The sequence here points instead to a place that accumulated meaning and use over generations, each phase built upon, and sometimes directly on top of, what came before.