Relaxing — deep, immediate muscle release.
Loaded with major ions — the essential minerals (Ca, Mg).
Dense, salty water — you float without effort.
Shima Onsen is a historic hot spring town on the Nakatsu river in the mountains of Gunma, designated a national health resort and set in a narrow gorge of great natural beauty where chloride-rich volcanic water from multiple sources fills the atmospheric wooden ryokan that line the traditional onsen street unchanged since the Meiji era. The Kashiwaya Ryokan is one of Shima's most celebrated traditional inns, offering the complete Japanese hot spring hospitality sequence of seasonal kaiseki cuisine, carefully prepared mineral baths, and yukata-clad evening strolls through the lantern-lit gorge town. Shima's therapeutic tradition dates back over 1,300 years, and the preserved wooden bathhouses and ryokan facades of its traditional street create one of Gunma's most atmospheric and photographically rewarding historic onsen townscapes.