The parish church of Beaumaris is a fourteenth-century Grade I listed building, founded at the same time as the town itself. It is a plain rectangular nave-and-chancel structure typical of Edwardian church-building, distinguished by its excellent fittings: a complete set of fifteenth-century misericords carved with figures and beasts, and an unusually fine alabaster effigy in the chancel.
The misericords — folding choir-stall seats that supported standing clergy during long services — are the chief attraction for medievalists. The figures are humorous and earthy, of a kind that priests would have seen but the congregation never did. In the side chapel is the stone coffin of Princess Joan, wife of Llywelyn the Great and natural daughter of King John, washed up here after the priory at Llanfaes was dissolved in 1539.