The oratory known as Teampall Bréanainn is the focal point of an Early Christian monastic settlement occupying the southern half of Inis Tuaisceart, a cliff-bound island of 241 acres lying four miles off the western tip of the Dingle Peninsula. The northern half of the island shows no trace of human settlement at all, as though the community had deliberately concentrated itself into one small, legible corner of a largely inhospitable place.

The settlement is not arranged as a single neat enclosure but as three irregular stone-walled compounds, each serving a distinct purpose. The two easternmost appear to have functioned as a cemetery area. The oratory shares its enclosure with a rough stone cross, one metre high and 75 centimetres across the arms, standing at the corner of a quartz-heavy mound beside the south wall, and a leacht, a type of commemorative stone platform used in early Irish monasticism, piled with quartz stones and set four metres to the east of the building. A second cross, noted in earlier descriptions as lying in the same pile of stones, has since gone missing. To the west, a large corbelled clochaun, a circular drystone beehive hut, survives to a height of nearly three metres internally, its floor sunk one and a half metres below the surrounding ground and its doorway opening onto a similarly sunken courtyard. The island was apparently uninhabited by 1756, but by 1838 the Kean family were living inside this very structure. A stone-lined grave on one of the upper terraces may date from that later period; it was not always possible to bring the dead to the mainland, and a child of the Kean family is recorded as having been buried on the island in the early nineteenth century. A holy well, Tobar Bréanainn, lies in the field to the north of the main enclosures, though it is now dry and the tradition of its holiness has faded to almost nothing.