Ikaho Rotenburo

Located at an elevation of around 700 meters on the slopes of Mt. Haruna in Takasaki, Gunma Prefecture, Ikaho Onsen is one of the region’s most celebrated hot springs, with a history so long that it appears in the Manyoshu, Japan’s oldest anthology of poetry. The Ikaho Rotenburo, a day-use open-air bath, allows visitors to enjoy Kogane-no-Yu (“Golden Hot Spring”)-the original source of Ikaho Onsen-in its pure, free-flowing form. Situated right at the spring’s source, the bath offers a rustic, open-air setting surrounded by untouched nature, where you can fully immerse yourself in this famous hot spring.

There are no washing facilities inside-only two open-air baths with different temperatures. The dense greenery around the baths gives the place a hidden-spring atmosphere that adds to its charm. The tea-brown mineral water is gentle on the skin and has long been cherished as a “fertility bath.”

On the path leading to the rotenburo, you’ll also find the only spot in Ikaho where you can actually drink the Kogane-no-Yu spring water. Rich in iron with a distinctive taste, it’s worth trying at least once. Nearby, there is also a viewing point where you can observe the spring water bubbling up from the earth.