Colwyn Bay is a town, community and seaside resort in Conwy County Borough on the north coast of Wales overlooking the Irish Sea. It lies …Colwyn Bay is a town, community and seaside resort in Conwy County Borough on the north coast of Wales overlooking the Irish Sea. It lies within the historic county boundaries of Denbighshire. At the 2021 census, the community had a population of 10,576, and the built up area had a population of 29,275. According to the tourist board, it is renowned for its 3 mile long sandy beach which has been enhanced with millions of tonnes of sand, so therefore 'man-made' and its permanently available irrespective of the tides.