The fourth sits a little higher on the mountain slope, and it is this outlying structure that is the most architecturally accomplished of the group. Together they occupy a bowl-shaped recess on the north-western slopes of Knocknadobar, looking out above Coonanna Harbour on the Iveragh Peninsula.

The upper hut is roughly square in plan, with an east-facing entrance just forty-five centimetres wide, and its walls are noticeably more carefully built than those of the three lower structures. Within them are three corbelled chambers, a construction technique in which stones are laid in progressively overlapping courses to form a self-supporting roof without mortar. Two of the chambers still retain their roofing lintels, flat capstones that have held their position for an unknown but considerable span of time. The hut stands just over a metre high, with walls nearly three-quarters of a metre thick, and the internal depth is 2.8 metres. Françoise Henry, writing in 1957, recorded the site and noted the quality of its construction, and the hut's details were later included in the 1996 archaeological survey of the Iveragh Peninsula compiled by Aidan O'Sullivan and John Sheehan. The date of the structures has not been firmly established, but corbelled stonework of this kind is associated with early medieval monastic and secular occupation in the west of Ireland, where communities sometimes sought out remote, marginal terrain deliberately.