What makes it unusual is not just its age or setting but its construction: the walls are built using the corbelling technique, in which courses of drystone are laid so that each slightly overhangs the one below, gradually closing the roof without mortar or timber. The hut measures just 3.8 metres by 3.3 metres, stands 1.4 metres high, and has walls 1.2 metres thick. An entrance less than a metre wide opens to the north, and inside, a wall-niche survives at the southern end while a secondary curving wall divides the interior. It is, in other words, a miniature but carefully considered piece of architecture.

Puffin Island, known in Irish as Oileán na gCánóg, lies off the south-west tip of the Iveragh Peninsula in County Kerry. The hut sits within what appears to be a larger enclosure of roughly 36 by 30 metres, the two structures likely contemporary with one another. The island takes its name from the seabird colonies that still breed there, but its archaeology points to a different kind of visitor: early Christian monks and hermits favoured such remote Atlantic islands precisely because of their isolation, and corbelled stone huts of this type are associated with that tradition elsewhere along the Kerry coastline, most famously on Skellig Michael. Whether this particular site served a monastic, pastoral, or other function is not certain, but its position commanding wide views from north-west to south suggests it was not placed without thought about what could be seen from it, and who or what might be approaching by sea.

The island is a designated nature reserve and access requires care and advance planning, as it is home to sensitive seabird populations during the breeding season. The hut sits in the south-west sector of the enclosure, above Boat Cove, and the views it commands, even today, give a strong sense of why this narrow shelf of rock above the water would have been chosen as a place worth building something that was clearly meant to last.