Hoshinoya Karuizawa

Karuizawa has been Tokyo's cool-air escape since the Meiji era, and Hoshino Resorts has been running hot springs in this valley for more than a century. Hoshinoya Karuizawa is the group's flagship here: a scatter of guest pavilions raised on stilts above a network of streams and ponds, laid out to feel like a hamlet rather than a hotel.

Rooms fall into water-facing, terrace and forest categories, all with the group's spare, timber-and-paper aesthetic. The Meditation Bath is the property's signature - a dim, half-submerged chamber where the only real sensations are warm water and echo - and the neighbouring Tombo-no-yu public bath has been in use since 1915.

The valley is a working conservation site as much as a resort, with wild bird sanctuaries and guided walks up towards Mount Asama. Dinner is a modern Japanese menu built on Shinshu produce, and the whole place is a little over an hour from Tokyo on the Hokuriku shinkansen.