To reach Baia di Sorgeto’s natural hot springs, bathers descend 200 stairs from the hamlet of Panza to the water’s edge. It’s a blazing September afternoon and I’m bobbing in 95-degree Fahrenheit hot ...

This year marked a huge turning point for hotel spas—the old model of putting a lonely string of treatment rooms next to a vaguely damp steam room has been decisively retired. And the most exciting ...