Most visitors, if they come at all, think of Mooghaun in terms of its great concentric ramparts. But within the inner enclosure, and in places actually built onto those ramparts, are stretches of drystone walling that belong to a different moment entirely, or perhaps several different moments, layered across the same ground.

Two walls in the south-eastern quadrant of the inner enclosure are considered likely ancient features. One of them runs southward for 22 metres from roughly the centre of the quadrant, then at its southern end turns sharply westward and continues along the very summit of the rampart itself. It is built from large limestone blocks, some set directly onto bedrock, others propped on smaller stones to keep them level, and up to three courses survive in places, reaching as much as 0.8 metres in height. The fact that one end was constructed on top of the rampart rather than before it means this wall post-dates at least that phase of the hillfort's life, though how much later is not straightforward to determine. Mooghaun hillfort is generally associated with the later Bronze Age, and the presence of field boundaries within and upon it points to a long history of agricultural use of the hill after whatever original defensive or ceremonial function the ramparts served. The work of researchers including Ewan Grogan, published across studies from 1995 into the 2000s, has mapped these walls and flagged their probable antiquity, while acknowledging that the hill preserves more than one phase of enclosure.