Nobesawa Silver Mine
Ginzan Onsen is best known as a picturesque hot spring resort, but its history began around 1600, when the area prospered as Nobesawa Ginzan (literally, “silver mine”), one of Japan’s largest silver mines. In its heyday in the mid-1600s this valley supported a community of approximately 15,000 people, many of whom worked in the mining industry. The mines were directly managed by the government.
Mining technology was primitive, and most of the digging and excavation was done by hand. Miners used an innovative technique called yakibori (literally “burn digging”) to speed up the work. Rocks were heated using charcoal, and once hot, they were doused with cold water. This made them brittle and easier to break, revealing the pockets of silver ore inside.
Nobesawa Ginzan’s silver boom was short-lived, and by 1689 the mines closed. Where there were once 53 mining tunnels, only one remains open to the public. Located in the mountains behind Ginzan Onsen along the hiking path through Shirogane Park, this 20-meter-long tunnel gives visitors the chance to observe the circumstances in which miners worked hundreds of years ago. The tunnel is cold year-round, and the blackened sections on the cave walls and floor are evidence of the yakibori mining technique.