What makes the site quietly arresting is not just its age but the inscription nearby. In the south-west corner of the same graveyard stands a cross-inscribed pillar bearing a Latin inscription to a man named Luguaedon, dated to the sixth or seventh century. It is one of the oldest Latin inscriptions in Ireland outside of ogham stones, those upright stones on which early Irish names and words were carved in a system of notched strokes along a central line.

The church itself is a conserved early Christian structure with a nave measuring roughly 5.5 metres long and 3.65 metres wide, oriented east to west in the standard fashion. A later chancel was added at the eastern end, smaller at 3.5 metres by 2.55 metres, indicating the building was extended and adapted over time. The west wall retains a trabeate doorway, meaning the opening is formed by two upright jambs topped by a flat horizontal lintel rather than an arch, a construction technique typical of early Irish ecclesiastical architecture. The east wall once held a window, though it has been robbed out, leaving only the gap. The Luguaedon pillar, sometimes called the Stone of the Son of Lugaedon, has drawn scholarly attention since at least the mid-nineteenth century, cited in works by Hardiman in 1846 and Kinahan in 1868, and the inscription connects the site to a figure said in tradition to have been a nephew of Saint Patrick.

The island is accessible by boat from Oughterard or Cong, and the church and graveyard are a short walk from the landing area along the island's central path. The pillar itself stands within the graveyard enclosure, and its inscription, worn but legible, reads down the stone in small Roman capitals.