Yamanashi Kai City
Natural free-flowing hot spring water and radon bathing that promotes remarkable sweating
"Ryuo Radon Onsen Yutopia" is a lodging and day-use hot spring facility in Kai City, Yamanashi Prefecture, that also accommodates therapeutic bathing stays. All baths feature natural hot spring water drawn from underground, a sulfur, sodium, chloride, and bicarbonate spring offered as free-flowing, directly sourced natural hot spring water. Its defining feature is the radon inhalation room, which fills the bathing area with radon gas. Unlike a typical sauna, it is known as an inhaled hot spring that delivers its ingredients through breathing and the skin, inducing remarkably intense sweating in a short time. It also has a refreshing cold plunge bath with an outdoor-bath feel, letting you enjoy an ultimate detox experience through alternating hot and cold bathing with the radon bath. Inside, the Showa-era retro atmosphere creates a soothing setting for a high-quality, restorative stay.
A natural hot spring supplied directly from the source, bubbling up from underground and sent to each bath. This famous spring has also been selected as one of the Yamanashi Top 100 Hot Springs and is rich in components such as sodium, chloride, and bicarbonate. Once you sink into the tub, your body is warmed thoroughly to the core and accumulated fatigue gently melts away. After bathing, your skin feels smooth, and you can fully experience a genuine sense of bathing and deep healing throughout your body.
A dedicated inhalation room filled with fresh radon gas supplied from a radon generator, unlike a typical sauna. By breathing in the gas that fills the room and absorbing it through the skin, it is known as an inhaled hot spring that promotes remarkably intense sweating even in a short time. It gently warms you from the core, and the ultimate detox experience of sweat flowing nonstop refreshes tired body and mind deeply.
A refreshing cold plunge bath that washes away the sweat drawn out to the limit by the radon bath and tightens your heated body. Designed for a cool-down with an open, outdoor-bath feel, lowering your well-warmed body into cold water brings a pleasant temperature contrast and an exceptional sense of relaxation. By alternating between the radon bath and the cold plunge bath, you can enjoy deep calm and a revitalizing feeling.
Availability and rates are shown on each booking site.
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JAPAN'S FINEST ONSEN & SAUNA
The Finest Onsen & Sauna in Japan
57 SELECTIONS
Most of what we surveyed never even made it onto this site. This book is a further cut from what did. Our editor bathed in every onsen and sauna in it, and wrote only what they confirmed on the ground.
