Shirafuneso Shintaku Ryokan

Shirahone's own-spring inn: seven free-flowing milky baths open round the clock, two free private baths with water welling up from below, and spring-water rice porridge in a clay pot — but the buildings are old, dinner is usually in a partitioned hall, and last check-in at 17:00 is firm

Shintaku Ryokan stands on a wooded rise on the east side of Shirahone, the mountain spa village on the road to Kamikochi, and its full name, Shirafunesō, keeps alive 'Shirafune' (white boat), the old name the inn says the village took from its milk-white tubs. The draw is the inn's own spring, Aratama-no-yu: about 50°C and 240–260 litres a minute, cooled only by adjusting the flow — no heating, added water or recirculation — and drinkable at every spout. It runs clear after cleaning and turns milky within three or four hours, crusting the old cypress tubs in white mineral. Seven tubs are fed: hinoki indoor baths and open-air baths for each sex, open 24 hours except a 10:00–12:00 clean, plus two free 45-minute private baths in an outbuilding where water bubbles up from beneath the tub. Japanese guests rate it 4.7 across 3,836 reviews on one site and 4.56 across 1,252 on another, with the baths at 4.8 and 4.67. Bloggers from 2023 to 2026 praise the water, the generous Shinshu kaiseki — apple gratin, salt-grilled iwana, Azumino soba, onsen-porridge croquettes, Japanese black beef with hoba miso — and a breakfast built around porridge cooked in the spring water. Autumn 2026 reviews add free room upgrades and a send-off with waved yellow handkerchiefs. The downsides: old buildings, a long walk and a slow lift to the baths, a dark path to the outdoor bath, dinner in a partitioned hall rather than a private room for most bloggers, courses served briskly, and a firm 17:00 last check-in — one October 2026 guest felt brushed off when phoning about running late. Two-meal rates run about ¥19,800–34,100 per person.