A bronzed, willowy veteran in black Speedos glides into the shallow, round-ish thermal pool snuggled into a grassy riverbank. It’s one of a huddle of rock pools, with trees and a modest wooden changing hut. We’re the only people here bathing beneath a cement-coloured sky that seems to inhale the steam billowing from the baths. It could be an onsen in rural Japan, except I’m about 10,000 miles from there, in north-west Spain.
