Known as Doonclaur, or Dún Cláir in Irish, it is what archaeologists classify as a multivallate rath, a type of ringfort defended not by one enclosing bank but by several concentric ones. Where most raths make do with a single bank and ditch, Dún Cláir has three earthen banks and two fosses, or ditches, between them, a level of elaboration that in early medieval Ireland typically signals a site of some social weight.

The engineering here repays close attention, even through the undergrowth. The inner bank, the most substantial of the three, rises 3.75 metres above its fosse and 2 metres above the interior ground level. The middle bank clears 3 metres above the outer fosse. The outermost bank is more modest, only present along the southern and eastern sides of the enclosure, standing about a metre above the external ground level and 2 metres above its own ditch. The interior measures roughly 28.5 metres north to south and 30 metres east to west. Along the inner faces of the banks, stretches of dry-stone masonry appear at intervals, where the earthen construction was reinforced with carefully laid stone. Entry to the interior is via a causewayed gap on the eastern side, the passage through the innermost bank lined with stones. Somewhere in the north-eastern sector of the interior there was once a souterrain, an underground passage or chamber of the kind often associated with early medieval settlement and storage, though it is no longer visible at ground level. The site appears in J. Cuppage's 1986 archaeological survey of the Dingle Peninsula under the name Doonclaur, and the Irish form of the name, Dún Cláir, meaning something like "fort of the plain" or "clear fort", suggests it was a landmark of some local significance long before anyone thought to record it systematically.