Yoshinoya Kosen

A 300-year-old mineral spring inn hidden at the bottom of a narrow valley in Iwaki, you descend through a residential area and suddenly find yourself somewhere that feels like deep mountains. The alkaline carbonated spring is said to help with neuralgia and joint pain. The bath itself is mixed for most of the day, with short windows set aside for women. The whole place has an unapologetically retro feel, with antiques, old plates, and the kind of character you either love or find not for you.