Yet when archaeologist M. J. O'Kelly excavated a semi-subterranean stone house on the eastern slope of Canroe, the highest point of Beginish Island, in the early 1950s, he found exactly that: carved into the underside of a lintel stone forming part of the entrance passage was a Norse inscription, read by Kavanagh as "LIR ERECTED THIS STONE; M... CARVED (THE) RUNES," and dated by him to somewhere between 1000 and 1100 AD. An equal-armed cross had been pocked into the same stone above the second word. The lintel is now held in a museum collection, but its presence here points to something genuinely unusual: a Hiberno-Viking community, living and farming on a Kerry island, leaving behind both Scandinavian objects and Scandinavian words.

The settlement complex on Canroe is extensive, comprising eight houses, fifteen cairns, eight animal shelters, and an elaborate network of field walls spreading from the western slope over the summit and down to the rocky eastern shoreline. O'Kelly's excavations revealed two main phases of Early Medieval occupation, separated by a layer of wind-blown sand roughly half a metre thick. The earlier phase left behind five houses, the bulk of the field walls, and fifteen cairns; the cairns, along with two querns found reused in a later building, suggest that tillage was practised here alongside stock-raising. Deposits of limpet and periwinkle shells were found associated with almost all the houses, pointing to a diet heavily supplemented from the sea. The second phase, probably not long after the first, produced the corbelled circular house with the runic lintel: a substantial structure eleven metres in external diameter, its walls standing to 3.5 metres, with timber roof supports anchored into sockets in the wall-face and a large central hearth. The bone assemblage from this later phase included ox, pig, sheep, fish, and sea-birds. Both phases ended the same way: sand accumulated rapidly, burying the structures and eventually forcing abandonment. The whole complex might have remained invisible indefinitely, had rabbits not been introduced to the island in the 1920s. Their burrowing stripped Canroe of its grass cover and exposed the houses and field system that O'Kelly would later excavate.