 The largely mountainous village of Besshi joined the city of Niihama in 2003 greatly increasing the size of the city.The Besshi copper mine (once considered to be one of the most productive in the world) jump-started the Sumitomo corporation.Even though the mine has since closed (its legacy is now preserved in a small museum and onsen attraction, Minetopia Besshi), Sumitomo remains a large presence in town.