CondeNast Traveller called the Spa at the Solage Calistoga the #1 spa in North America and the Caribbean and the #10 spa in the entire world. It's no surprise then, that everything there is pretty much perfect--the atmosphere, their approach to health and wellness, and the treatments. Oh my, the treatments. Like everywhere else in Napa, seasonality rules, and they take care to include herbs, fruits and vegetables that grow locally (think sage and lavender body polishes and pumpkin and papaya facials in autumn). Their signature treatment is the "mudslide," a three part series that begins at their "mud bar," where a mud body masque is specially concocted for you with minerals and essential oils. The next step is a relaxing and rehydrating soak in geo-thermal mineral water, and the final phase is a lounge in a state of the art vibration chair to restore harmony.