Kosenjo

Iwate Ichinoseki City

Kosenjo is a bathing facility located in Ichinoseki City, Iwate Prefecture. This long-established business, founded in 1951, underwent significant sauna facility renovations under the leadership of the fourth-generation owner, Hiromi Asano, after 2020, attracting attention from sauna enthusiasts nationwide. It offers two types of saunas: a high-temperature sauna using natural lava from Mount Chokai and a herbal sauna newly established in the summer of 2022, providing different sweating experiences. The cold plunge bath, using well water drawn from underground, tightens the body with its soft water quality and pleasant coldness. The outdoor air bath space is an open area with a courtyard, allowing you to slowly relax your body, which has been thoroughly steamed with self-löyly. A restaurant and banquet hall are also attached, allowing you to enjoy a meal after the sauna.

Hot Spring & Bath Information

Bicarbonate Ion Spring (Artificial Hot Spring)

TypeArtificial Hot Spring

An artificial hot spring bicarbonate ion spring using minerals. It is expected to have beauty and detox effects, recommended for dieting and metabolism improvement. After deep sweating in the sauna, soaking in this hot spring further promotes the elimination of unnecessary metabolic waste. It is effective for preventing adult diseases through improved blood circulation, and alleviating shoulder stiffness, back pain, muscle pain, and joint pain. It is also expected to increase immunity and improve issues like aging odors. It has a wide range of benefits, including improving skin roughness, burns, cuts, and numbness in hands and feet. It also works to improve poor blood circulation due to stress and arteriosclerosis, refreshing both body and mind.

Sauna

Lava Sauna (High-Temperature Sauna)

100°C

Sauna TypeDry Sauna

Stove TypeConvection Stove (Sauna Stone)

Capacity6people

Men's

A lava sauna where self-löyly is possible. The sauna stones use natural lava from Mount Chokai, and the floor is also made of rock, allowing for excellent heat transmission. You can enjoy löyly with aroma water carefully selected by the fourth-generation president, a sauna enthusiast, every day, promoting deep sweating with your preferred scent and humidity. The gentle heat unique to natural lava envelops the entire body, warming it from the core and effectively boosting metabolism.

Herbal Sauna

90°C

Sauna TypeHerb Sauna

Stove TypeConvection Stove (Sauna Stone)

Capacity10people

Men's

A herbal sauna newly established in August 2022, infused with the spirit of the fourth-generation president. It is highly acclaimed, attracting sauna enthusiasts from all over the country. The steam filled with herbal medicine fills the room, providing relaxation effects along with its unique aroma. Unlike the lava sauna, it gently warms the body with mild heat.

Cold Bath

Cold Bath

18°C

Water QualityNatural Water (Groundwater, Spring, etc.)

Capacity6people

Flow-through
Men's

A cold plunge bath using well water drawn from underground. It is characterized by its very soft water quality and pleasant texture. Featuring a unique design where water flows vigorously from a lion's mouth, it is visually enjoyable as well. The water temperature remains stable throughout the year, crisply tightening the body heated by the sauna. With the refreshing and soft qualities unique to groundwater, it places little burden on the body even with prolonged immersion. After thoroughly warming up in the high-temperature sauna or herbal sauna, entering this well water cold plunge bath brings a sense of refreshment and deep relaxation.

Business Hours

Monday
10:00〜21:30
Tuesday
10:00〜21:30
Wednesday
10:00〜21:30
Thursday
10:00〜21:30
Friday
10:00〜21:30
Saturday
10:00〜21:30
Sunday
10:00〜21:30
Holiday
10:00〜21:30

Closed Days: None

Address

78-2 Akaogi Sakai, Ichinoseki City, Iwate Prefecture

Onsen & Spa Facilities (Super Sento, Sauna, Spa)

Gender Access

Gender Separated

Tattoo Policy
No tattoo-specific restriction
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