Okutone Onsen

Okutone Onsen is located in Naganohara Town, Gunma Prefecture, in the Agatsuma River valley above the vast Nozori Lake reservoir, where the dam-created mountain lake provides both a dramatic scenic backdrop and a source of hydroelectric power for Gunma's highland communities. The siliceous thermal waters here are part of the geothermal richness of the Agatsuma volcanic corridor, which leads toward the famous Kusatsu Onsen — one of Japan's greatest spa towns — through a succession of highland valleys, volcanic landscapes, and traditional hot spring communities. Bathing at Okutone Onsen offers a peaceful pause in a highland landscape where the mirror surface of Nozori Lake reflects the surrounding mountains and forests, providing one of Gunma's most scenically beautiful mineral spring settings in a valley shaped by both volcanic forces and human engineering.