Mitake Onsen Kiso Valley Nagano

Mitake Onsen in the Kiso Valley, Nagano prefecture, draws sulfurous thermal waters along the ancient Nakasendo Highway — one of the five great Edo-period roads connecting the capital to the provinces — where the Kiso valley's 11 post towns (juku) including the exceptionally preserved Naraijuku, Tsumago, and Magome have maintained the character of Edo-period highway inns for over 400 years. The Kiso Valley's extraordinary forest of hinoki cypress and kiso sugi cedar — some stands dating to the 13th century — was so valuable to the Owari Tokugawa domain that illegal felling was punishable by death, creating Japan's first systematic forest preservation law (Owari sanpō), and the valley's timber-craft tradition continues in Kiso lacquerware and woodworking. Bathing in sulfurous onsen after hiking the Nakasendo's cobblestone mountain path between post towns — where the road's stone paving and cedar forests remain unchanged from the 17th century — creates a uniquely immersive encounter with Edo-period highway culture and Japanese mountain hot spring tradition.