River Oyunuma Natural Footbath

This is an open-air footbath set right into the Oyunumagawa walking trail, a short stretch of forest path that runs near the Taisho Jigoku steam vents outside Noboribetsu Onsen town. The water comes straight from Oyunuma, a hot spring pond uphill, which overflows and cools as it runs downstream, creating a natural pool warm enough to soak tired feet in.

There's no building, counter, or locker room here — just a stretch of stream-fed water along the trail where hikers and onsen-town visitors stop, take off their shoes and socks, and sit for a while with their feet in the warm current. The surrounding area is wooded, so the stop doubles as a quiet break during a forest walk rather than a standalone spa visit.

Admission is free, which fits the low-key, drop-in nature of the spot. There's no staffed reception or fixed schedule tied to the footbath itself; it's accessed as part of the Oyunumagawa trail network, so plan around daylight and trail conditions rather than posted opening hours. Because it's a natural, unheated, un-gated feature, water temperature and flow can shift with weather and season, so it's worth checking current conditions with the Noboribetsu tourism office before making a special trip.

It works well paired with a walk to Taisho Jigoku or Oyunuma itself, since all three sit along the same trail system. Bring a towel and be ready to go barefoot on uneven ground near the water.