Mostyn is a village and community in Flintshire, Wales, and electoral ward lying on the estuary of the River Dee, located near the town of Holywell. It has a privately owned port that has in the past had a colliery and ironworks and was involved in the export of commodities, and in present times services the offshore wind industry and shipped the wings for the Air…Mostyn is a village and community in Flintshire, Wales, and electoral ward lying on the estuary of the River Dee, located near the town of Holywell. It has a privately owned port that has in the past had a colliery and ironworks and was involved in the export of commodities, and in present times services the offshore wind industry and shipped the wings for the Airbus A380 which were manufactured at Broughton.