The island, Inis Tuaisceart, lies four miles off the western tip of the Dingle Peninsula and two and a half miles north of the Great Blasket. Its 241 acres are ringed entirely by sea-cliffs, and the northern half of the island holds no evidence of human settlement whatsoever. Only the southern portion, where a small field system survives, shows any sign that people once lived and worked here.

The settlement is associated with St. Brendan, the sixth-century monk renowned in early Irish tradition for his extraordinary sea voyages. It would have been typical of the ascetic impulse that drew early Christian communities to remote and difficult places along the Irish Atlantic coast, where isolation was understood as a spiritual condition. Within this cluster of remains, a stone cross stands as part of the site. A second cross was once recorded here too, described in the Ordnance Survey Memoirs as lying in a pile of stones, possibly associated with a leacht, which is a low cairn-like memorial mound used for prayer or commemoration. That second cross has since gone missing and its whereabouts are unknown. The island itself rises from under 100 feet on its south-eastern side to a maximum altitude of 573 feet near the north-western ridge, the land thin-soiled and rocky throughout, which gives some sense of what any early monastic community would have been contending with.