The Sado Gold and Silver Mine has a long history, and according to descriptions in the Konjaku Monogatarishu (Tales of Times Now Past and Present) from the Heian period, it has been known as an island where gold dust could be mined since at least the 12th century. The Aikawa Gold and Silver Mine was opened in 1601, and as it became a direct territory of the Edo Shogunate and development progressed, it became Japan's largest gold and silver mine, boasting one of the world's largest production volumes. The gold and silver produced at the Sado Gold and Silver Mine was used as currency, and was transported from Sado and Aikawa to Ogi, then by sea, before being unloaded at Izumozaki Port, along the main Hokkoku Kaido route, and then from Oiwake-juku (present-day Karuizawa) via the Nakasendo road to Edo Castle, supporting the Shogunate's finances.
The transportation route, which covered a total distance of approximately 400 kilometers to Edo, was called the "Golden Road" or "Mountain Cargo Road," and many historical and cultural sites remain along the route.