100% natural hot spring black water and a Hokutolite bath. Exceptional relaxation in a cold plunge bath with flowing spring water
Kanagawa Yokohama City
"Washinoyu" is a bathing facility in Kanagawa Ward, Yokohama City, Kanagawa Prefecture, that boasts natural hot spring water gushing from approximately 200 meters underground. Two large baths with different atmospheres, "Noten-no-Yu" and "Shinrin-no-Yu," are available on alternating days for men and women. Its biggest highlight is the 100% natural hot spring black water source, passed through Hokutolite from Akita Prefecture's Tamagawa Onsen. It also offers a "high-concentration carbonated spring" that blends this black water with highly concentrated carbon dioxide, strongly supporting beautiful skin and overall health. The sauna is a genuine dry type with excellent perspiration, and the cold plunge bath luxuriously uses the black water source as flowing water straight from the spring. This smooth cool-down experience, wrapped in the components of the hot spring, is truly worthy of being called a "town bathhouse for therapeutic bathing."
TypeNatural Hot Spring
A brownish natural hot spring gushing from approximately 200 meters underground. Offered as Hokutolite Bath, passed through rare Hokutolite, it is rich in mineral components that help smooth and soften the skin. There is also a bath that blends it with highly concentrated carbon dioxide, allowing you to enjoy the spring's mineral benefits and the circulation-boosting effects of carbonation at the same time for a luxurious bathing experience.
Sauna TypeDry Sauna
Stove TypeInfrared Heater
Capacity10people
A genuine dry sauna with excellent perspiration, where you can fully feel the heat. The softly lit room offers the perfect space to quietly sweat while facing yourself. Just outside the sauna room is the facility's signature cold plunge bath with flowing spring water, allowing for a smooth and powerful hot and cold contrast bath.
Water QualityHot Spring Water
Capacity4people
The facility's own black hot spring water is used luxuriously as flowing water straight from the source, without being heated. Its smooth feel, derived from the hot spring minerals, and the fresh, refreshing sensation unique to source water are its defining features. Offering an exceptional cool-down experience that is distinctly different from a typical cold bath, it lets you enjoy the benefits of this skin-beautifying spring with your whole body.
Closed Days: None
Melbeau Yokohama Koyasuy 151-151 Nanashima-cho, Kanagawa Ward, Yokohama City, Kanagawa 221-0061
Gender Access
Gender Separated
Curated by an expert who visits onsen and sauna facilities every day and has explored 300+ locations — only facilities confirmed to be truly exceptional are featured.
Learn more
100% natural hot spring black water and a Hokutolite bath. Exceptional relaxation in a cold plunge bath with flowing spring water
Kanagawa Yokohama City
"Washinoyu" is a bathing facility in Kanagawa Ward, Yokohama City, Kanagawa Prefecture, that boasts natural hot spring water gushing from approximately 200 meters underground. Two large baths with different atmospheres, "Noten-no-Yu" and "Shinrin-no-Yu," are available on alternating days for men and women. Its biggest highlight is the 100% natural hot spring black water source, passed through Hokutolite from Akita Prefecture's Tamagawa Onsen. It also offers a "high-concentration carbonated spring" that blends this black water with highly concentrated carbon dioxide, strongly supporting beautiful skin and overall health. The sauna is a genuine dry type with excellent perspiration, and the cold plunge bath luxuriously uses the black water source as flowing water straight from the spring. This smooth cool-down experience, wrapped in the components of the hot spring, is truly worthy of being called a "town bathhouse for therapeutic bathing."
TypeNatural Hot Spring
A brownish natural hot spring gushing from approximately 200 meters underground. Offered as Hokutolite Bath, passed through rare Hokutolite, it is rich in mineral components that help smooth and soften the skin. There is also a bath that blends it with highly concentrated carbon dioxide, allowing you to enjoy the spring's mineral benefits and the circulation-boosting effects of carbonation at the same time for a luxurious bathing experience.
Sauna TypeDry Sauna
Stove TypeInfrared Heater
Capacity10people
A genuine dry sauna with excellent perspiration, where you can fully feel the heat. The softly lit room offers the perfect space to quietly sweat while facing yourself. Just outside the sauna room is the facility's signature cold plunge bath with flowing spring water, allowing for a smooth and powerful hot and cold contrast bath.
Water QualityHot Spring Water
Capacity4people
The facility's own black hot spring water is used luxuriously as flowing water straight from the source, without being heated. Its smooth feel, derived from the hot spring minerals, and the fresh, refreshing sensation unique to source water are its defining features. Offering an exceptional cool-down experience that is distinctly different from a typical cold bath, it lets you enjoy the benefits of this skin-beautifying spring with your whole body.
Closed Days: None
Melbeau Yokohama Koyasuy 151-151 Nanashima-cho, Kanagawa Ward, Yokohama City, Kanagawa 221-0061
Gender Access
Gender Separated
Curated by an expert who visits onsen and sauna facilities every day and has explored 300+ locations — only facilities confirmed to be truly exceptional are featured.
Learn more