When the antiquarian Charles Smith visited in 1756 he recorded the ruins of what he called a very ancient church, but whatever he saw has since disappeared entirely, absorbed back into the headland or lost beneath later burials. The ground it occupied, a small promontory called Rinn an Chaisleáin, carries the memory of a castle too, and a piece of tooled masonry turned up during a grave-digging at some point in the past, though whether it belonged to the church or the castle, nobody can say with certainty.

The possibility that a medieval ecclesiastical record might anchor this site to a documented history has not held up well under scrutiny. A church listed as "Eccia de Inse" in the Papal Taxation of 1302 to 1307, compiled for the diocese of Ardfert, was proposed in the late nineteenth century as a reference to a foundation on the Great Blasket. The more persuasive reading, however, places that entry at Inch, east of Annascaul on the mainland, making the island church a site without a name in any surviving document. What does survive, and what makes Rinn an Chaisleáin quietly significant, is the burial ground itself. It was unconsecrated ground, which in Irish practice meant it served as the burial place for those excluded from the churchyard: unbaptised infants, the victims of shipwreck, and those who had died by suicide. These margins of society left their marks in low upright stones and drystone-built graves, several of which remain visible today, plain and unornamented, arranged without the formality of a consecrated cemetery.