Shibu no Jigokudani Geyser

The Shibu no Jigokudani geyser near Yamanouchi emits a continuous plume reaching 20 meters, fed by water above 90 degrees Celsius rich in sodium, sulfur, and calcium sulfate. Unlike interval geysers, this one flows without pause, requiring periodic clearing of mineral deposits around the vent. Before the source was piped to local baths, this valley reportedly rumbled with multiple geysers filling the air with steam and sulfur. Across the Yokoyu River, Kōrakukan inn has operated since 1864. Its riverside baths drew young macaques to play in the water, and park officials eventually solved that problem by building the monkeys their own dedicated bath at Jigokudani Wild Snow Monkey Park.