 With access to local coal deposits and a harbour that could take advantage of Cornwall's copper mines and the copper deposits being extracted from the largest copper mine in the world at Parys Mountain on Anglesey, Swansea developed into the world's major centre for non-ferrous metal smelting in the 19th century.The second metal industry to expand in Wales was iron smelting, and iron manufacturing became prevalent in both the north and the south of the country.In the north of Wales, John Wilkinson's Ironworks at Bersham was a significant industry, while in the south, a second world centre of metallurgy was founded in Merthyr Tydfil, where the four ironworks of Dowlais, Cyfarthfa, Plymouth and Penydarren became the most significant hub of iron manufacture in Wales.