"known as the Church in the Sea. It is to be found on a small tidal St Cwyfan's Church, the Church-in-the-Seaisland called Cribinau located off the west coast of Anglesey and close to the village of Aberffraw. Also known as Llangwyfan the church can be reached on foot at low tide. Old maps show the church standing on the mainland of Anglesey but erosion by the sea of the boulder clay cliffs has since separated the church from the mainland"