Perched on the edge of a steep ravine above the Iya River, this upscale hot springs inn is absolute luxury in the middle of nowhere. Iya Onsen is one of Japan's three "secret" baths (if you ask locals where the other two are, nobody seems to know). Stay here for sweeping views from most guest rooms, the lavish meals, and the riverside hot spring bath accessed by cable car. When the mist rises from the valley in the early morning, it really does feel like you're in a hidden world. If you're not staying here, there are lunch-and-bath options starting from ¥2,500. The staff will pick up overnight guests from Oboke Station.