Noboribetsu

Noboribetsu delivers the most dramatic onsen experience in Hokkaido, set above the volcanic Hell Valley where nine distinct spring types emerge. This variety lets you soak in sulfur for skin ailments, then step to a sodium bicarbonate bath for muscle recovery, all within a 10-minute walk of the valley's steam vents. The resort's 15 ryokan accommodate over 2,000 guests nightly, making it the region's largest thermal destination.