Around Kai Hills Country Club × Stays Highly Rated for AccessibilityRecommended Hotel·Ryokan

Since its opening in 1980, we have cherished and preserved the medicinal Onsen known as "The Best Radon Onsen in the East." This extraordinary hidden hot spring is located in Kai City, Yamanashi Prefecture, where you can still enjoy the radon Onsen just as it was when it first opened. While it may lack modernity and pristine aesthetics, the spring water has remained fresh and unchanged for over 40 years. Awarded second place nationwide in the Health Promotion category of the 2022 Onsen General Election. It is a genuine 100% pure flowing Onsen, said to account for only 2% of all Onsens across The whole country.