The Spa at Inness Resort

Floor-to-ceiling windows frame the Catskills and Shawangunks from inside a hammam-style bathhouse that somehow manages to feel warm despite being genuinely stark. This spa at the Inness resort runs about 7,000 square feet, with a saltwater pool for warmer months and the kind of severe, expensive minimalism that ends up being more inviting than intimidating. Vogue put it on their 100 Best Spas in the World list, which tracks.