The Iwami Ginzan silver mine lies in a narrow, forested valley in Shimane Prefecture, on the Sea of Japan side of western Honshu, and the site called Iwami-jo is a reminder that the silver here was worth fighting for. Iwami-jo, also known as Yamabuki Castle, was a mountain fortress perched on a ridge above the mining district, and for much of the sixteenth century the great regional clans, first the Ouchi, then the Amago and finally the Mori, struggled to control it. The mine was a source of wealth and power, and whoever held the castle held the silver.
The silver itself transformed this part of Japan. Large-scale mining began in the 1520s, when new refining techniques from Korea made it possible to extract silver more efficiently, and by the early seventeenth century the mine was producing a huge share of Japan's output, and Japan in turn supplied a notable fraction of the world's silver. European mapmakers of the time marked this region as the silver mines. The site was listed by UNESCO in 2007, partly because the mine left so little scar on the landscape; the forest has grown back over the workings.
The riding here is a calm affair. Approaches to the mining district are narrow country roads through cedar forest, with a few tight bends and a lot of shade, and the speed limits are low. The town of Oda, about ten kilometres away, has fuel, shops and restaurants, and it is the place to fill up before heading into the valley. In the old district, car access is limited, and you are expected to park at a visitor lot and walk or cycle.
The ride goes on from here toward Itsukushima Shrine on Miyajima, a long day across the Chugoku mountains, so plan for an early start. Autumn is spectacular, with red maples against dark cedar, and spring brings fresh green. Summer is humid, and the winter coast can be grey and wet. Take a rain jacket in any season, since the weather off the Sea of Japan changes fast.