Yahazu-jo is another mountain castle site in the hills behind Omori, among the ridges that guarded the Iwami silver mines, and it adds up to the same story as its neighbour Yataki-jo, but with its own angle. Where one site is about watching a valley, this one is about the chain: a series of small fortresses linked by ridgeline paths, so that smoke or a signal fire could pass a warning along the hills. Silver paid for armies in the sixteenth century, and whoever held the mountains held the mines. The castles were mostly built of earth and timber, and what remains are ditches, flat platforms and the shape of old gateways, now overgrown with cedar, oak and bamboo grass.
Reaching it is a country ride more than a destination. The roads climb out of the Omori and Odachō valleys in short steep runs, and in places the surface turns patchy, with moss on the shady side and fallen leaves in autumn. There are few guardrails and no real shoulders. A single narrow lane may serve three farmhouses and a shrine. Timber trucks use some of the routes, so listen on blind corners. Traffic is sparse, but whatever comes is large.
The nearest sizeable town is Odachō-oda, fourteen kilometres away, where you will find fuel, a supermarket and a handful of eateries. Gotsu on the coast is the other option, a bit further. If you have time, the old town of Omori is worth walking through, a single long street of tiled merchant houses, small cafes and shrines, with a gentle slope and almost no traffic. The silver mine tunnel at Ryugenji Mabu is open to walkers, and the cool air inside is welcome in summer.
Nature here is deep Chugoku mountain forest. Macaques are sometimes seen, boar leave their rooting in the damp soil, and the dawn chorus in May and June is loud. Snakes sun themselves on warm tarmac in summer. If you stop to look around, give the ground a glance before you step. Autumn is lovely, with red maple and golden ginkgo, but the light goes quickly, so plan to be down from the hills by late afternoon.