That chamber, just 1.65 metres long, 0.85 metres wide, and 0.85 metres high, is covered by a lintel stone, making it a kind of miniature room-within-a-room, enclosed and concealed in the very fabric of the structure.

Corbelling is a technique in which stones are laid in overlapping courses, each projecting slightly inward over the one below, eventually closing the space above without the need for mortar or timber. It is one of the oldest building methods in Ireland, used across millennia from prehistoric tombs to early medieval monks' cells. The hut at Baile Na Bhfionnúrach measures 3.7 metres in diameter internally and stands to a surviving height of 1.9 metres. The small lintelled chamber within the wall thickness is an unusual feature; in similar structures elsewhere on the Dingle Peninsula, such recesses were likely used for storage, though their precise function here is not recorded. The site was documented by J. Cuppage in the 1986 Corca Dhuibhne archaeological survey, a landmark study of the extraordinarily dense concentration of early remains across this part of west Kerry.