Yukawa Onsen Kappa no Yu, in Chino, Nagano prefecture, features thermal water at 40°C across an indoor bath, an outdoor rotenburo bath and a sauna, for a quiet break.
Insider tip — Kappa no Yu in Chino celebrates the playful kappa water spirit said to inhabit the mountain streams feeding Lake Suwa, the largest lake in Nagano. The Suwa region was historically one of Japan most important silk and precision instruments manufacturing centres, and Seiko Watch museum is nearby.