"Bagno Vignoni The location: Bagno Vignoni, a hamlet in the province of Siena well-known for its dramatic hot springs, overlooking Val d'Orcia, a UNESCO World Heritage Site since 2004 Top amenities: Thermal swimming pools, sauna, steam bath, holistic spa One of the most unique places to stay on this list, Hotel Adler Thermae makes use of its location on Tuscany's hot springs in the most delicious way possible—by providing a compound of thermal swimming pools, baths, and spas full of travertine grottoes, stalactites, and stalagmites, for guests to luxuriate in. Staying somewhere like this is one of those wish list travel experiences most people only dream about. The resort has plenty of other things going for it too, though: a glass-roofed restaurant, stellar wine list, and in-room terraces, to name a few." - Alex Erdekian