NaturalHotSpringSashikinoEjinnoYu

A supreme natural hot spring wrapped in 5-million-year-old amber, 100% free-flowing from the source

Okinawa Nanjo City

"Natural Hot Spring Sashiki no Ejin no Yu" is a scenic hot spring facility inside Yuinchi Hotel Nanjo in Nanjo City, Okinawa. It offers amber-colored "fossil seawater" that springs from strata about 2,000 m underground and from layers dating back about 5 million and 54 million years, delivered as 100% free-flowing natural spring water with no dilution, heating, or filtration at all. You can enjoy its richly mineralized water for its skin-beautifying effects, along with a one-of-a-kind bathing experience marked by a distinctive petroleum-like aroma. The sauna is also powerful, featuring a dry sauna with strong heat from a double heat source and a cold plunge bath around 15°C. With a panoramic view of Nakagusuku Bay from the hilltop, it is a place where you can free your mind and body to the blessings of ancient times.

Hot Spring & Bath Information

Natural Hot Spring Sashiki no Ejin no Yu

TypeNatural Hot Spring

Flow-through

A 100% free-flowing natural hot spring that wells up from about 2,000 m underground and from strata dating back tens of millions of years, with no dilution, heating, or filtration. This amber, cloudy, richly mineralized strong saline spring is rich in iodine and salt, and is known for its excellent warming and skin-beautifying effects. The source water has a distinctive oil-like aroma, giving the sensation of bathing in an ancient sea. From the panoramic windows of the indoor bath, you can enjoy a spectacular view of Nakagusuku Bay while bathing.

Sauna

Dry Sauna

100°C

Sauna TypeDry Sauna

Stove Typeconvection

Capacity15people

Men'sWomen's

One of Okinawa's most powerful saunas, using a double heat source of gas far-infrared and an electric stove. The room heats up to around 100°C, driving intense sweating with a forceful blast of heat. There is plenty of bench space for relaxed lounging, and on weekends, staff-led löyly service is offered as well. With the aroma of wood blending with the scent of the amber-colored spring water, this facility offers a uniquely memorable sauna experience.

Mist Sauna (Women Only)

52°C

Sauna TypeMist Sauna

Capacity6people

Women's

A mildly heated mist sauna attached to the women's bath area. Moist, enveloping steam surrounds your entire body, gently warming you while leaving your skin soft and hydrated. It is easy to enter even for those who do not like high-temperature saunas, and you can relax at your own pace in a quiet space.

Cold Bath

Cold Plunge Bath

16°C

Water Qualitytap

Capacity5people

Men'sWomen's

A crisp, cold plunge bath located just outside the sauna room. With a stable water temperature of around 15°C to 18°C, it rapidly cools down a body heated by the powerful sauna and tightens the skin. It is spacious and deep enough for a proper cooldown, then you can move on to outdoor air bathing while feeling the hilltop breeze.

Business Hours

Monday
06:30〜23:00
Tuesday
06:30〜23:00
Wednesday
06:30〜23:00
Thursday
06:30〜23:00
Friday
06:30〜23:00
Saturday
06:30〜23:00
Sunday
06:30〜23:00
Holiday
06:30〜23:00

Closed Days: None

Address

1688 Sashiki Arakaki, Nanjo City, Okinawa

Hotel & Ryokan

Gender Access

Gender Separated

🚫
Tattoo Policy
No Tattoos
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