St Gwenfaen`s well lies on a spectacular stretch of coast path between Borthwen, near Rhoscolyn, and Rhoscolyn Head. It has one of the most well preserved well chambers on Anglesey. St Gwenfaen lived in the 6th century and founded a church nearby. Most of the well`s stonework lies below ground level.Steps lead down into a chamber with seats in front of a pool. There was a tradition that the well cured mental illness, and quartz stones were thrown into the well as an offering.