We spent a night here after reading a lot about thermal spas all over Tuscany, but the cave experience is really what intrigued us the most. Our room came with half-off the Grotto, so my wife and I gleefully scheduled a time slot, followed by a couples massage. First of all, it should be noted that the spa and the hotel feel a little like two totally different sides of the same building. I even got incredibly lost trying to make my way back to my room.
We started in the thermal pool outside, which was fairly empty. It felt a little like a big outdoor hotel pool, except people were just sort of soaking instead of swimming. The water was warm, but not hot like a hot tub. Nice, but nothing especially "luxurious" if that's what you're looking for.
When it came time for our cave visit, we stopped at a small locker area where we changed into a basic gown type thing, not wearing anything underneath. We were told we had 1 hour. Then, we walked downward, through a doorway, into the caves, which are basically divided into three sections: a cool area, a mild area, and a hot area. We walked all the way to the back, to the hottest zone, were a few people here and there languished on recliners in silence. My wife and I did the same, and found the experience to be surprisingly relaxing -- unlike a sauna or steam room, we weren't "enduring" the heat, but rather entranced by it. Things remained silent for the most part, until an older group got up to leave and spend a good while chatting loudly in Italian with total disregard. Wish the rule about silence was reiterated to guests before they entered. After our hour was up, we went back upstairs, got our clothes from the locker, and were guided to an area to shower. We read some reviews that mentioned getting hosed down naked by staff members, but this didn't happen at all to us -- we had or own private rooms. Maybe the policy changed, so fear not about having to be naked in front of anyone throughout this experience. Overall, truly unique and I'm glad we did it -- although not sure I'd have been quite as excited had we payed full price.
Our couples massage was really nice as well, although it's a "relaxation massage" -- don't expect them to work out any muscle issues, but instead basically rub your body with oil for the duration. We had to wear tiny little paper thongs (nothing else), so like most massages, you'll need be comfortable with that. Both our massage therapists were women, very polite, spoke little english. Definitely very very relaxed afterward, as advertised.
Overall, the hotel itself was just fine. It seems to me that the cave/spa is what makes the place really special, and I think it's worth a visit for sure if you're willing to spend a little money for a full day of treatments/pool time.
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