Trefriw is a village in Conwy, Wales, lying a few miles south of the site of the Roman camp of Canovium. It is situated in Snowdonia, beside the River Conwy.

The village is known for its woollen mills , and for the nearby chalybeate spa , first known to have been used by the Romans and further developed in about 1700 its Waters are one of very few throughout Europe to have been classified as a medicine due to their high iron content.