Tomogaura Road (Entrance to Yamabuki Castle)
Located on a lush hillside some distance from the closest buildings, the starting point of the 7.5-kilometer road between Iwami Ginzan and the port of Tomogaura can be difficult to spot. In the latter half of the sixteenth century, this was the epicenter of the entire silver mine. Known as the Sannai settlement, it centered on an administrative facility where officials overseeing the mine were based. Nearby stood the miners’ homes, shops, and several temples, each with its own cemetery. In this period, the mine was ruled first by the Ouchi family, which established the Tomogaura Road and built the Yamabuki Castle on high ground just outside the settlement. This hilltop fortress served to protect the mine and the road during an epoch of constantly shifting alliances and rivalries among local warlord-led families.
The Ouchi lost their stronghold and eventually conceded control over the silver mine itself to the Mohri family in 1562, but Yamabuki Castle and Sannai maintained their central position in the mining community for another four decades. In 1600 Iwami Ginzan was taken over by the Tokugawa clan, who three years later went on to unify the entire country under their banner, establishing the Tokugawa shogunate that was to rule Japan until 1867. The new government abandoned Sannai, choosing to establish its center of control in the Omori area at the foot of the mountain. The town of Omori then developed around this magistrate’s office (daikansho), while the flow of silver was directed away from the coast, to be carried instead over land to the port at Onomichi and from there to Osaka and Edo (present-day Tokyo).
Today only the stone foundations remain. The site of Yamabuki Castle, from where you can look out over the coastline of the Sea of Japan, has been reclaimed by nature. But the Tomogaura Road can still be traveled, allowing you to imagine the massive effort needed to haul heavy loads of ore through the forests on foot more than 400 years ago.