
MONTHLY RANKING
From among the onsen and sauna facilities across Japan that I actually visited in March 2026, I comprehensively evaluated the quality of the sauna, the cold plunge bath, the mineral composition of the natural hot spring, the outdoor bathing environment, the food, the overall atmosphere of the facility, and the service, and am introducing the facilities that left the strongest impression in a ranking format.
Facilities Listed
10facilities
Last Updated
2026.5.28

MONTHLY RANKING
From among the onsen and sauna facilities across Japan that I actually visited in March 2026, I comprehensively evaluated the quality of the sauna, the cold plunge bath, the mineral composition of the natural hot spring, the outdoor bathing environment, the food, the overall atmosphere of the facility, and the service, and am introducing the facilities that left the strongest impression in a ranking format.
Facilities Listed
10facilities
Last Updated
2026.5.28
Last Updated
2026.5.28
Saga Tara Town
A hot spring and bathing facility in Tara Town, Fujitsu District, Saga Prefecture, with full ocean views overlooking Ariake Sea and Mount Fugen. The Gravity Sauna, carved from solid spruce wood, and the Grid Sauna using Japan's first AINO heater are superb, and the deep cold plunge bath filled with natural groundwater flowing directly from the Tara Mountain Range can be entered while standing. When you totonou on the terrace while feeling the sea breeze, it feels as if even the moon's gravity is flowing through your body. The best sauna, cold plunge bath, and outdoor bathing experience in life are here. Before I knew it, I was letting out a shout, and this is an addictive facility.
View DetailsNagano Tateshina Town
A scenic resort onsen and sauna facility at an elevation of 1,400m in Tateshina Town, Kitasaku District, Nagano Prefecture, overlooking Lake Shirakaba. The sauna, where you can enjoy aroma auto-löyly every 30 minutes, and the cold plunge bath at around 12°C fed by water from Tateshina-yama are superb. From the observation sauna Ku, which feels as if it were floating on the lake, you can look out over Lake Shirakaba and Mount Kuruma, and in the infinity open-air bath you can feel the wind. I was keenly reminded that natural beauty cannot be artificially created, and I was simply left speechless. Even the natural spring water drink after bathing is included, making this a facility where you can savor gifts from the Earth with your whole body.
View DetailsNagano Matsumoto City
A famous public bath in Matsumoto City, Nagano Prefecture, equipped with nano water and a wide variety of saunas. In the men's bath, Otokomae SAUNA offers auto-löyly, while Arigato SAUNA offers Nagano Prefecture's first self löyly. The 13-14°C pot-style cold plunge bath, Hitori Mizu, can be drunk straight from the source, and when you feel the wind during outdoor bathing, your skin starts to tingle and settle into perfect balance. I visited after a stop at Zuisho, and the flow of quietly receiving heat before sinking into cold spring water was superb. This is an addictive facility that ends a trip with the best possible final strike.
View DetailsYamanashi Yamanakako Village
A lodging-style resort hotel in Yamanakako Village, Minamitsuru District, Yamanashi Prefecture, offering views of Mount Fuji and Lake Yamanaka from an altitude of about 1,100m. You are thoroughly steamed in the löyly sauna, and the Mount Fuji natural water cold plunge bath is cool in a way that seems to gently envelop your body. The spectacular views from the open-air bath and the outdoor bathing chairs are wonderful, and even on a misty morning, just being in this place lifts your spirits. Although Mount Fuji could not be seen that day, I was still fully totonou thanks to the natural water cold plunge bath and the authentic sauna. This facility is packed with extraordinary heat experiences that even turn an invisible landscape into anticipation.
View DetailsSaga Takeo City
An outdoor sauna facility in Takeo City, Saga Prefecture, where you can experience the Five Elements philosophy in the middle of a forest. The three saunas, wood, metal, and fire, each have their own character, and the heat from the wood-burning stove and the crackling of the campfire gently loosen the mind. The natural underground water cold plunge bath, fed directly from the source, is soft, and from the rooftop or the forest-surrounded outdoor bathing area, you can feel Takeo's breeze all over your body. Simply letting sweat flow while being embraced by nature gives the sensation of shedding layers of distractions one by one. This is a superb facility that sharpens all five senses and can only be experienced here.
View DetailsWakayama Shirahama Town
An impressive onsen resort hotel in Shirahama Town, Nishimuro District, Wakayama Prefecture, where the sea and palace-like architecture merge. Its appeal lies in the high-temperature sauna with self-löyly and the two onsen salons where you can enjoy Shirahama Onsen's source water. The sweets and drinks enjoyed in the lounge Musee, which overlooks Tanabe Bay, are also superb, and the luxury of every room having an ocean view really sinks into your body. I was simply overwhelmed by the scale of the 40 billion yen total construction cost, and being wrapped in onsen and architectural beauty made reality feel distant. A one-of-a-kind facility where you can bathe in extraordinary experience in its entirety.
View DetailsSaga Takeo City
A superb hotel bathing facility in Takeo City, Saga Prefecture, harmonized with Takeo's nature and designed for totonou. It offers four types of sauna, including one using a custom wood-burning stove and Bonatherm, and another using kiln materials from Kuromuta ware, plus an outstanding 150cm-deep cold plunge bath that you can submerge your head in. Soaking in the alkaline simple hot spring Bihada no Yu at pH 9.15 and enjoying the outdoor bathing area with the crackling sound and fragrance of burning wood is wonderful. It's worth taking a taxi here even from 7 a.m. This is an addictive relaxation facility that makes you forget the hustle and bustle of everyday life.
View DetailsYamanashi Tsuru City
An inn in Tsuru City, Yamanashi Prefecture, where you can enjoy lodging, onsen, and sauna as one integrated experience. The auto-löyly sauna heats you up at once, and the 14-16°C cold plunge bath fed by a direct flow of source water and underground water cools you all the way to your core. Soak in the gentle sulfuric spring water and your skin becomes moist and beautifully balanced, while the outdoor bathing space lets your breathing deepen. The idea of mixing onsen water into the cold plunge bath is simply amazing. It's smooth and cold, yet somehow feels enveloping. Once you know this sensation, it becomes a facility you will want to stop by again and again during any trip.
View DetailsShizuoka Shizuoka City
A superb facility in Suruga Ward, Shizuoka City, Shizuoka Prefecture, called a sacred site of sauna. You can work up a sweat in one go in the 110°C Showa-style strong high-temperature dry sauna, and in the herbal sauna blended by a Korean medicine doctor, you are wrapped in rich steam and fragrance. The 100% natural water cold plunge bath is medium-soft water with a hardness of 84, gentle enough to drink and cools the body kindly. I was moved by how delicious the water was when gulping it down, and before I knew it, I felt like my consciousness was about to drift away. This is truly a sacred facility where you can bathe your whole body in natural water, and it is addictive.
View DetailsYamanashi Fujiyoshida City
An experiential bathing facility in Fujiyoshida City, Yamanashi Prefecture, where you can enjoy heat, cold, and rest in a seamless flow. You can thoroughly heat your body in the sauna and then reset it all at once in the Mount Fuji natural water cold plunge bath. The natural hot spring in the open-air and indoor baths envelops your skin with its mineral content, and in the silence your breathing deepens. I arrived still carrying the regret of not being able to see Mount Fuji at Hotel Mt. Fuji, but here that feeling was instantly rewarded. For a day-use facility, this level of completion is almost unfair.
View DetailsOut of 18 facilities visited in 3/2026, we've selected the top 10 in this ranking.
Last Updated
2026.5.28
Saga Tara Town
A hot spring and bathing facility in Tara Town, Fujitsu District, Saga Prefecture, with full ocean views overlooking Ariake Sea and Mount Fugen. The Gravity Sauna, carved from solid spruce wood, and the Grid Sauna using Japan's first AINO heater are superb, and the deep cold plunge bath filled with natural groundwater flowing directly from the Tara Mountain Range can be entered while standing. When you totonou on the terrace while feeling the sea breeze, it feels as if even the moon's gravity is flowing through your body. The best sauna, cold plunge bath, and outdoor bathing experience in life are here. Before I knew it, I was letting out a shout, and this is an addictive facility.
View DetailsNagano Tateshina Town
A scenic resort onsen and sauna facility at an elevation of 1,400m in Tateshina Town, Kitasaku District, Nagano Prefecture, overlooking Lake Shirakaba. The sauna, where you can enjoy aroma auto-löyly every 30 minutes, and the cold plunge bath at around 12°C fed by water from Tateshina-yama are superb. From the observation sauna Ku, which feels as if it were floating on the lake, you can look out over Lake Shirakaba and Mount Kuruma, and in the infinity open-air bath you can feel the wind. I was keenly reminded that natural beauty cannot be artificially created, and I was simply left speechless. Even the natural spring water drink after bathing is included, making this a facility where you can savor gifts from the Earth with your whole body.
View DetailsNagano Matsumoto City
A famous public bath in Matsumoto City, Nagano Prefecture, equipped with nano water and a wide variety of saunas. In the men's bath, Otokomae SAUNA offers auto-löyly, while Arigato SAUNA offers Nagano Prefecture's first self löyly. The 13-14°C pot-style cold plunge bath, Hitori Mizu, can be drunk straight from the source, and when you feel the wind during outdoor bathing, your skin starts to tingle and settle into perfect balance. I visited after a stop at Zuisho, and the flow of quietly receiving heat before sinking into cold spring water was superb. This is an addictive facility that ends a trip with the best possible final strike.
View DetailsYamanashi Yamanakako Village
A lodging-style resort hotel in Yamanakako Village, Minamitsuru District, Yamanashi Prefecture, offering views of Mount Fuji and Lake Yamanaka from an altitude of about 1,100m. You are thoroughly steamed in the löyly sauna, and the Mount Fuji natural water cold plunge bath is cool in a way that seems to gently envelop your body. The spectacular views from the open-air bath and the outdoor bathing chairs are wonderful, and even on a misty morning, just being in this place lifts your spirits. Although Mount Fuji could not be seen that day, I was still fully totonou thanks to the natural water cold plunge bath and the authentic sauna. This facility is packed with extraordinary heat experiences that even turn an invisible landscape into anticipation.
View DetailsSaga Takeo City
An outdoor sauna facility in Takeo City, Saga Prefecture, where you can experience the Five Elements philosophy in the middle of a forest. The three saunas, wood, metal, and fire, each have their own character, and the heat from the wood-burning stove and the crackling of the campfire gently loosen the mind. The natural underground water cold plunge bath, fed directly from the source, is soft, and from the rooftop or the forest-surrounded outdoor bathing area, you can feel Takeo's breeze all over your body. Simply letting sweat flow while being embraced by nature gives the sensation of shedding layers of distractions one by one. This is a superb facility that sharpens all five senses and can only be experienced here.
View DetailsWakayama Shirahama Town
An impressive onsen resort hotel in Shirahama Town, Nishimuro District, Wakayama Prefecture, where the sea and palace-like architecture merge. Its appeal lies in the high-temperature sauna with self-löyly and the two onsen salons where you can enjoy Shirahama Onsen's source water. The sweets and drinks enjoyed in the lounge Musee, which overlooks Tanabe Bay, are also superb, and the luxury of every room having an ocean view really sinks into your body. I was simply overwhelmed by the scale of the 40 billion yen total construction cost, and being wrapped in onsen and architectural beauty made reality feel distant. A one-of-a-kind facility where you can bathe in extraordinary experience in its entirety.
View DetailsSaga Takeo City
A superb hotel bathing facility in Takeo City, Saga Prefecture, harmonized with Takeo's nature and designed for totonou. It offers four types of sauna, including one using a custom wood-burning stove and Bonatherm, and another using kiln materials from Kuromuta ware, plus an outstanding 150cm-deep cold plunge bath that you can submerge your head in. Soaking in the alkaline simple hot spring Bihada no Yu at pH 9.15 and enjoying the outdoor bathing area with the crackling sound and fragrance of burning wood is wonderful. It's worth taking a taxi here even from 7 a.m. This is an addictive relaxation facility that makes you forget the hustle and bustle of everyday life.
View DetailsYamanashi Tsuru City
An inn in Tsuru City, Yamanashi Prefecture, where you can enjoy lodging, onsen, and sauna as one integrated experience. The auto-löyly sauna heats you up at once, and the 14-16°C cold plunge bath fed by a direct flow of source water and underground water cools you all the way to your core. Soak in the gentle sulfuric spring water and your skin becomes moist and beautifully balanced, while the outdoor bathing space lets your breathing deepen. The idea of mixing onsen water into the cold plunge bath is simply amazing. It's smooth and cold, yet somehow feels enveloping. Once you know this sensation, it becomes a facility you will want to stop by again and again during any trip.
View DetailsShizuoka Shizuoka City
A superb facility in Suruga Ward, Shizuoka City, Shizuoka Prefecture, called a sacred site of sauna. You can work up a sweat in one go in the 110°C Showa-style strong high-temperature dry sauna, and in the herbal sauna blended by a Korean medicine doctor, you are wrapped in rich steam and fragrance. The 100% natural water cold plunge bath is medium-soft water with a hardness of 84, gentle enough to drink and cools the body kindly. I was moved by how delicious the water was when gulping it down, and before I knew it, I felt like my consciousness was about to drift away. This is truly a sacred facility where you can bathe your whole body in natural water, and it is addictive.
View DetailsYamanashi Fujiyoshida City
An experiential bathing facility in Fujiyoshida City, Yamanashi Prefecture, where you can enjoy heat, cold, and rest in a seamless flow. You can thoroughly heat your body in the sauna and then reset it all at once in the Mount Fuji natural water cold plunge bath. The natural hot spring in the open-air and indoor baths envelops your skin with its mineral content, and in the silence your breathing deepens. I arrived still carrying the regret of not being able to see Mount Fuji at Hotel Mt. Fuji, but here that feeling was instantly rewarded. For a day-use facility, this level of completion is almost unfair.
View DetailsOut of 18 facilities visited in 3/2026, we've selected the top 10 in this ranking.