Isoya Onsen Onsenato no Noyugun

Where a hot spring inn once stood near Hakodate, demolished in 1985, volunteers have channelled the spring water that keeps flowing from the old source into pools dug along the riverbank. There are two distinct waters here: a white sulfur spring and a more transparent bicarbonate-sodium spring, both free and unmanaged. You can smell the sulfur before you see the place, which adds to the sense of arriving somewhere genuinely wild.