Overnight Stays

Stay at Zenshichinoyu in Zao Onsen. An extremely acidic pH 1.5 sulfur spring, five distinct private baths, and an all-you-can-drink dinner plan.

Stay at Katsuranoyu Marunaga Ryokan in Shirahone Onsen. A snowy mixed-gender outdoor bath, a mineral-crusted private bath, and two milky sulfur springs.

Stay at Niseko Goshiki Onsen, a hidden mountain ryokan at 750m elevation with a strongly acidic sulfur spring that shifts color daily and views of Mt. Annupuri.

Stay at Furofushi Onsen in Aomori, where an hourglass-shaped mixed-gender outdoor bath sits right at the edge of the wild Sea of Japan. Full access & bathing guide.

Stay at Hikage Onsen, a modern hidden ryokan on the Akita-Aomori border. Milky white sulfur baths, private open-air pools, and refined Akita cuisine in deep snow country.

Stay at Nakadanasou in Komoro, Nagano — a historic ryokan famed for its seasonal apple bath, silky low-temperature spring, and refined kaiseki cuisine. Full access guide from Tokyo.