Or in Welsh: Eglwys bach y môr. Dating from the 12th century, it survives the sea storms only with the help of some robust 19th century defences. Erosion has reduced the peninsula on which it was originally built to a tidal island known as Cribinau. You can find it along the Coastal Path just north of Aberffraw (Anglesey).
The church itself is dedicated to the Irish Saint Cwyfan (Kevin) who lived in the 6th century. Whether he ever visited Anglesey is not known, but the island, once the stronghold of the Celtic Druids until the Roman invasion, was certainly a favoured retreat for early Christian hermit-saints.
You can walk across to the island at low tide and the church is still used for weddings and christenings. Come a bright summer’s day, it would be hard to imagine a more momentous setting for such important family rites.