I've heard of some pretty spectacular spas, but nothing like Grotta Giusti Natural Spa Resort. A nineteenth-century villa set in a private park, it's the very picture of elegance, but the real draw is the ancient grotto underneath it.
Part of the Monsummano Terme, near Florence and Pisa, the hotel boasts both a modern wellbeing center, complete with thermal pools and hydro-massages, and a large underground grotto.
The caves have three zones, amusingly named Paradise, Purgatory and Hell. As you pass through them, the heat and humidity intensify, though it never exceeds 34°C. The steam of the thermal waters is said to benefit all kinds of ailments.
It's a totally natural underground thermal bath, discovered in 1849 when miners noticed steam escaping through a hole in the ground. Since then, visitors have spent hours detoxing there among the stalactites and stalagmites. RM
Images: Grotta Giusti