Japan is blessed with onsens all over the country. However, many are of questionable quality. Togura Kamiyamada's is a sulfur hot spring, and is the real deal. We recently had a couple of guests who exemplified just how good our onsen is.
Over the weekend, we hosted a 91-year old lady who had to be wheelchaired from the lobby to her guest room due to weak legs. However, the next morning, she walked to the lobby. I asked about the wheelchair, and she said that thanks to soaking in our mineral bath, her legs felt good enough to walk!
Another guest had a rare allergy. Her research said our onsen would be good for her condition, so she came to stay the night. The next morning when I went to put away her futons, she was sound asleep. Apparently her allergy usually causes her to wake up every two hours, but thanks to our onsen she didn't wake up at all. She even decided to extend her stay 2 nights.
We don't say that Kamiyamada Onsen is a cure-all, but we can say with certainty that it is the real deal.
More on Kamiyamada Onsen's effects here.