Barmouth is a seaside town and community in the county of Gwynedd, northwestern Wales, lying on the estuary of the Afon Mawddach and Cardigan Bay. Located in the historic county of Merionethshire, the Welsh form of the name is derived from aber and the river's name, "Mawddach". The English form of the name is a corruption of the earlier Welsh form Abermawdd. The community includes the tiny villages of Llanaber, Cutiau, and Caerdeon.