Historic Sites Osarizawa Mine

Osarizawa Mine is a museum in Kazuno showcasing an extensive underground copper mining operation. The site preserves tunnel networks, mining equipment, and work areas that reveal how people extracted ore from the earth.

The mine began around 708 CE when copper was first discovered in the mountains, and it remained in operation for over 1200 years. Its closure in 1978 ended one of Japan's longest-running mining operations.

The Shishi Daikongon shrine here connects mining work to the discovery of copper in the region. Visitors can sense how people linked their daily labor underground to sacred traditions.

Visitors walk through sections of the tunnels on marked paths, though some passages are narrow and require careful movement. Bring sturdy footwear and a light jacket, as underground temperatures stay cool year-round.

For centuries, this was Japan's primary source of copper, shaping entire regional economies. What remains visible today is how mining dictated underground architecture, from worker dormitories to ore processing areas.