Pension Alphorn

Pension Alphorn is a small, family-run pension in Norikura Kogen, its interior built around a Swiss-chalet feel (the name comes from the Swiss alphorn). The water is Norikura Kogen Onsen (乗鞍高原温泉), a milky-white sulfur spring that's kept flowing fresh into four named private baths. They're free for guests and open on a first-come basis: hang the "in use" sign on the door, no reservation needed, any hour of the day or night. Two of the four are open-air, two are indoor. Takenoyu (岳の湯) pairs a tub for up to four people with a small roofless one-person tub for watching the moon and stars, with Norikura-dake in view on clear days. Hoshinoyu (星の湯) is a hinoki-wood tub reached along a stepping-stone path through a flower garden, lit deliberately low so the night sky stands out. Seseraginoyu (せせらぎの湯) and Tsukinoyu (月の湯) both have heated-floor washing areas and a partition that opens the room into a half-open-air bath. The pension itself has been run by the same family across two generations.