Even in wine country, where a stunning resort and spa lurks behind every twist in the road, Spa Solage is a standout for many reasons. Chief among them are the seductive farmhouse-style buildings, mud baths, a hydrotherapy circuit and geothermal pools, a nod to the healing nature of Calistoga's natural hot springs that bring visitors from around the world. A recent overhaul has resulted in additions such as a new indoor-outdoor relaxation lounge and an herb garden, whose crops will be incorporated into treatments.
Signature service: Solage Signature Mudslide, where you get to sidle up to the mud bar to select your own dirt. Can be enjoyed solo or as part of a couple or group.