Grotta Giusti, a 19th-century villa and the former home of poet Giuseppe Giusti, guards what he and composer Giuseppe Verdi considered to be the eighth wonder of the world — a 130-year-old thermal cave with an underground hot-spring lake. The only way to explore this unique formation is with an underground cave dive. Three qualified instructors ensure complete safety while guiding guests into the water and through the curious underwater cave systems. Without fins, divers are able to climb as well as swim through the cave. The key section is a cleft in the rock running at approximately 20 to 30 degrees off vertical. The main pass-throughs are at 32ft, 60ft and 90ft — and are breathtakingly beautiful, offering sights unlike anywhere else on earth. The clear waters reveal ancient stalagmites and stalactites, and the super-brave can even swim in total darkness — fully submerged between winding cave tunnels, there’s a second cave that is only accessible by traveling through the underwater system.
Junior Suite from $900 per night, underground cave dive $125 per person. Contact Eleonora Bellini, personal travel adviser, eleonora.bellini@ihchotels.it, +39 057 857 2333, grottagiustispa.com