Llansadwrn is a small village in the community of Cwm Cadnant in south-east Anglesey, in north-west Wales. It lies between Menai Bridge, Pentraeth and Beaumaris. It is named after the church, founded in the 6th century by Saint Saturninus, who together with his wife, is commemorated by an early Christian monument. Until 1984, Llansadwrn was a community.