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ACIDIC

Acidic Springs: Powerfully Antibacterial Waters for Skin Conditions

Published May 5, 2026·1min read

Acidic springs contain hydrogen ions at 1 mg/kg or more (typically pH 2–3). Their strong antibacterial action is indicated for atopic dermatitis, plaque psoriasis, and epidermoid suppuration. Note: contraindicated for sensitive skin and elderly guests with dry skin — always confirm before bathing.

Acidic Springs: Powerfully Antibacterial Waters for Skin Conditions
Analysis records
23 records
Prefectures
3 prefectures
Table of Contents
  1. What is an Acidic Spring?
  2. Indications for Bathing
  3. How to Bathe in an Acidic Spring
Acidic spring onsen
Yuyado Tokinoniwa
群馬県 Kusatsu
Photo: Partner facility

What is an Acidic Spring?

An acidic spring contains hydrogen ions (H⁺) at 1 mg per kilogram of spring water, creating strongly acidic water at roughly pH 2–3 — similar to lemon juice or vinegar. Most are found near volcanic areas; Kusatsu Onsen (Gunma) and Tamagawa Onsen (Akita) are the most famous examples.

The water has very strong antibacterial power; bathing may cause a tingling sensation on the skin, and the water tastes sour. They have traditionally been used as balneotherapy destinations for skin conditions and athlete's foot.

Indications for Bathing

  • Atopic dermatitisThe spring's strong bactericidal effect, with a pH of 2–3, may help suppress pathogens like Staphylococcus aureus that can worsen symptoms. It also has a keratolytic effect that promotes skin turnover. Bathing should be avoided during acute flare-ups and started with short durations during remission, always after consulting a dermatologist.
  • Plaque psoriasisAcidic water's powerful disinfectant properties are thought to help by strongly suppressing the growth of bacteria on the skin's surface. This action may support the improvement of the chronic inflammation associated with this condition.
  • Epidermoid suppurationThe highly acidic nature of the water provides a strong bactericidal effect. This may help manage conditions involving skin surface bacteria by suppressing their growth and supporting the improvement of chronic inflammation.
  • Impaired glucose tolerance (diabetes)This is one of the four official indications for bathing in acidic springs, as designated by Japan's Mineral Spring Analysis Method Guidelines. The strong acidity is believed to provide various therapeutic benefits.

How to Bathe in an Acidic Spring

  1. First-timers: start with 3–5 minutes and monitor your skin before extending the soak.Acidic springs are highly stimulating and can cause a stinging sensation due to their low pH. Their strong sterilizing action, while beneficial, can be intense for first-timers or those with sensitive skin. Starting with a brief soak allows your skin to acclimate and helps you monitor for excessive irritation.
  2. After bathing, rinse lightly with fresh water — residual acid can be overly irritating.While the spring's acidity offers potent sterilizing effects during your bath, leaving it on your skin can lead to irritation or dryness. A light rinse with fresh water helps neutralize any residual acid, protecting your skin from over-stimulation and ensuring a comfortable post-bath experience.
  3. Shampoo and face wash in a separate bathroom — they react with the acidic water.The onsen's water is strongly acidic, while soaps and shampoos are typically alkaline. Mixing them causes a chemical reaction that neutralizes the soap, preventing it from lathering and reducing its cleansing ability. For effective washing, always use the separate, fresh-water showers provided.

Related Onsen Facilities

16 matches
Yuyado Tokinoniwa Sulphur Spring
Sulphur SpringAcidic SpringChloride SpringSulphate SpringVerified
Yuyado Tokinoniwa
湯宿 季の庭
Gunma Kusatsu· わたの湯1Kusatsu Onsen
The Cotton-Wrapped Spring

This rare, naturally gushing source emerges from beneath 'Gensenkaku,' nestled beside Kusatsu Onsen's iconic Yubatake (Kusatsu's central hot-water field). Despite its strong acidity, its waters offer a remarkably soft bathing sensation, akin to being enveloped in silk floss. The milky-white waters, renowned for having Kusatsu's finest 'yunohana' (hot spring minerals), gently embrace the skin, contributing to silky skin and providing a restorative warmth that lingers deep within the body. Known as a 'phantom spring' for its history of disappearing once during the Taisho era, it now offers a profound escape from daily life, inviting deep relaxation and rejuvenation.

Onsen RyokanPrivate Rental BathRoom with Open-air Bath
StimulationBactericidalSkin BeautyHeat RetentionRelaxation
pHStrongly Acidic2.1
0714
TEMP50.2
0℃50℃100℃
KEY MINERALS
44.3 mg/kg

Strong astringent action that tightens skin. A key component of acidic springs, suited to oily or acne-prone skin.

The source of the distinctive sulfur smell. Dilates blood vessels via skin and inhalation to strongly boost circulation.

9.6 mg/kg

Mild antibacterial action keeps the skin clean. Trace transdermal absorption supports tooth and bone health.

Check Availability & Rates
PRIncludes affiliate links
Kusatsuonsen Sen Acidic Spring
Acidic SpringChloride SpringSulphate SpringInfo pending
Kusatsuonsen Sen
草津温泉 千
Gunma Kusatsu· 万代鉱Kusatsu Onsen
Scalding Strong Acidic Spring

The Mandaiko source, originating from traces of past mining development, is deeply intertwined with Kusatsu Onsen's unique yumomi culture and its long history of toji (therapeutic bathing). Its highly acidic waters, among Japan's most potent, deliver a distinctive tingling sensation, awakening both mind and body and offering a sense of rejuvenation. The high-temperature blessings penetrate deep into the core, leaving you with a surprisingly light and refreshed feeling after your bath. We invite those seeking a genuine toji experience, a true escape from daily life to restore their mind and body, to discover the profound power of this spring.

Onsen RyokanPrivate Rental BathTattoo OK (public bath)
StimulationBactericidalSkin BeautyHeat RetentionRelaxation
pHStrongly Acidic1.75
0714
TEMP94.6
0℃50℃100℃
KEY MINERALS
43.2 mg/kg

Strong astringent action that tightens skin. A key component of acidic springs, suited to oily or acne-prone skin.

25.1 mg/kg

Mild antibacterial action keeps the skin clean. Trace transdermal absorption supports tooth and bone health.

A natural moisturizer also used in skincare lotions. Forms a thin veil on the skin to reduce moisture loss after bathing.

Check Availability & Rates
PRIncludes affiliate links
Gouraonsen Kiritani Hakonesou Acidic Spring
Acidic SpringSulphate SpringChloride SpringVerified
Gouraonsen Kiritani Hakonesou
桐谷 箱根荘
Kanagawa Hakone· 大涌谷温泉 (2号・3号線混合泉)Hakone Onsen
The Turbid Water of the Earth's Pulse

This unique created hot spring utilizes the fumaroles of Owakudani, which were formed by volcanic activity approximately 3000 years ago. In the early Showa period, Hakone Onsen Kyokyu Co., Ltd. developed this source to supply hot water to areas like Sengokuhara and Gora. The water, created by mixing volcanic gas and water, offers a distinct, tingling, and tightening sensation upon contact with the skin. The powerful energy from the earth delivers restorative warmth deep into the body, a warmth that lingers long after your bath. It is ideal for those seeking deep relaxation and rejuvenation, wishing to refresh their mind and body.

Onsen RyokanPrivate Rental BathRoom with Open-air Bath
StimulationBactericidalSkin BeautyHeat RetentionRelaxation
pHStrongly Acidic2.1
0714
TEMP60.6
0℃50℃100℃
KEY MINERALS
7.5 mg/kg

Tightens the skin and balances sebum.

A natural moisturizer also used in skincare lotions. Forms a thin veil on the skin to reduce moisture loss after bathing.

14.2 mg/kg

A trace component with gentle antibacterial and anti-inflammatory action.

Check Availability & Rates
PRIncludes affiliate links
Kusatsu Kan Sulphur Spring
Sulphur SpringAcidic SpringChloride SpringSulphate SpringInfo pending
Kusatsu Kan
草津館
Gunma Kusatsu, Agatsuma District· 白旗源泉1Kusatsu Onsen
Shirahata-no-yu of Kusatsu

Shirahatage Genzen, located in Kusatsu Onsen and adjacent to Yubatake (Kusatsu's central hot-water field), is said to have been discovered by Minamoto no Yoritomo. Historically, it served as the stage for 'Jikan-yu' (timed bathing), supporting balneotherapy culture, and is truly considered the soul of Kusatsu. Its distinctive aroma and powerful waters, which feel as though they firm the skin, seem to awaken the mind and body from within. Surrendering to its embrace offers a pure moment to shed daily clamor and rediscover one's true self. This spring is a sanctuary for those seeking a fresh start and rejuvenation.

Onsen Ryokan
StimulationBactericidalSkin BeautyHeat RetentionRelaxation
pHStrongly Acidic2
0714
TEMP51.9
0℃50℃100℃
KEY MINERALS
47.1 mg/kg

Strong astringent action that tightens skin. A key component of acidic springs, suited to oily or acne-prone skin.

The source of the distinctive sulfur smell. Dilates blood vessels via skin and inhalation to strongly boost circulation.

10.0 mg/kg

Mild antibacterial action keeps the skin clean. Trace transdermal absorption supports tooth and bone health.

Check Availability & Rates
PRIncludes affiliate links
Noboribetsu Onsen Manseikaku Ferruginous Spring
Ferruginous SpringSulphur SpringAcidic SpringSimple SpringInfo pending
Noboribetsu Onsen Manseikaku
登別温泉 万世閣
Hokkaido Noboribetsu· 登別温泉 1号乙泉Noboribetsu Onsen
Hot Spring Department Store

Noboribetsu Onsen, Hokkaido's renowned hot spring, often called a 'department store of hot springs,' began its formal history in the Edo period when Takimoto Kinzo established a therapeutic bath. Despite the rugged landscape of 'Jigokudani' (Hell Valley), an explosive crater site said to be home to demons, the waters, a bounty from this earth, are filled with powerful healing. This acidic, sulfur-scented spring water thoroughly cleanses the skin and delivers restorative warmth deep into the body. It is highly recommended for those who wish to feel the energy of nature and experience a dynamic rejuvenation of mind and body.

Onsen RyokanRoom with Open-air Bath
StimulationBactericidalSkin BeautyHeat RetentionRelaxation
pHStrongly Acidic2.3
0714
TEMP72.5
0℃50℃100℃
KEY MINERALS
29.1 mg/kg

Strong astringent action that tightens skin. A key component of acidic springs, suited to oily or acne-prone skin.

The source of the distinctive sulfur smell. Dilates blood vessels via skin and inhalation to strongly boost circulation.

21.3 mg/kg

A trace component with gentle antibacterial and anti-inflammatory action.

Check Availability & Rates
PRIncludes affiliate links
Kusatsuonsen Ichii Acidic Spring
Acidic SpringChloride SpringSulphate SpringSulphur SpringInfo pending
Kusatsuonsen Ichii
ホテル一井
Gunma Kusatsu· 万代鉱1Kusatsu Onsen
The Strongest Spring from the Mine

The Bandaiko source, which unexpectedly erupted from within the Bandai Sulfur Mine in 1970, now stands as Kusatsu's primary hot spring, boasting the largest output and supporting the town. Named with the wish for 'eternal prosperity' (万代), this powerful source was born in the mountains, far from the Yubatake (Kusatsu's central hot-water field). Its colorless, transparent waters deliver a stimulating tingle that awakens both mind and body, while its robust warmth permeates to the very core. This energetic spring is a perfect companion for those seeking liberation from daily routines and a crisp mental and physical rejuvenation.

Onsen Ryokan
StimulationBactericidalSkin BeautyHeat RetentionRelaxation
pHStrongly Acidic1.7
0714
TEMP94.6
0℃50℃100℃
KEY MINERALS
43.2 mg/kg

Strong astringent action that tightens skin. A key component of acidic springs, suited to oily or acne-prone skin.

25.1 mg/kg

Mild antibacterial action keeps the skin clean. Trace transdermal absorption supports tooth and bone health.

A natural moisturizer also used in skincare lotions. Forms a thin veil on the skin to reduce moisture loss after bathing.

Check Availability & Rates
PRIncludes affiliate links
Noboribetsu Onsen Sulphur Spring
Sulphur SpringChloride SpringCarbonated SpringFerruginous SpringAcidic SpringSimple SpringInfo pending
Noboribetsu Onsen
滝乃家
Hokkaido Noboribetsu· うまの湯3Noboribetsu Onsen
Historic Noboribetsu Healing Waters

Nestled in Noboribetsu Onsen, famously called the "Department Store of Hot Springs" and rooted in the Ainu "Nupur-pet" (deeply colored river), the historic "Uma no Yu" source has flowed since Taisho 6 (1917). Its faint sulfur aroma gently unwinds the mind and body. The waters, softly enveloping the skin, warm the body to its core, providing restorative warmth that lingers. Overlooking a beautiful Japanese garden, this tranquil spring offers deep relaxation, a serene escape from daily commotion.

Onsen RyokanRoom with Open-air Bath
StimulationBactericidalSkin BeautyHeat RetentionRelaxation
pHNeutral6.4
0714
TEMP62.3
0℃50℃100℃
KEY MINERALS

The source of the distinctive sulfur smell. Dilates blood vessels via skin and inhalation to strongly boost circulation.

28.0 mg/kg

A trace component with gentle antibacterial and anti-inflammatory action.

A natural moisturizer also used in skincare lotions. Forms a thin veil on the skin to reduce moisture loss after bathing.

Check Availability & Rates
PRIncludes affiliate links
Rabisuta Kusatsuhiruzu Acidic Spring
Acidic SpringChloride SpringSulphate SpringSulphur SpringInfo pending
Rabisuta Kusatsuhiruzu
ラビスタ草津ヒルズ(共立リゾート)
Gunma Kusatsu· 万代鉱2
Scalding Strong Acidic Spring

The Mandaiko source, originating from traces of past mining development, is deeply intertwined with Kusatsu Onsen's unique yumomi culture and its long history of toji (therapeutic bathing). Its highly acidic waters, among Japan's most potent, deliver a distinctive tingling sensation, awakening both mind and body and offering a sense of rejuvenation. The high-temperature blessings penetrate deep into the core, leaving you with a surprisingly light and refreshed feeling after your bath. We invite those seeking a genuine toji experience, a true escape from daily life to restore their mind and body, to discover the profound power of this spring.

Onsen RyokanPrivate Rental BathRoom with Open-air Bath
StimulationBactericidalSkin BeautyHeat RetentionRelaxation
pHStrongly Acidic1.75
0714
TEMP94.6
0℃50℃100℃
KEY MINERALS
43.2 mg/kg

Strong astringent action that tightens skin. A key component of acidic springs, suited to oily or acne-prone skin.

25.1 mg/kg

Mild antibacterial action keeps the skin clean. Trace transdermal absorption supports tooth and bone health.

A natural moisturizer also used in skincare lotions. Forms a thin veil on the skin to reduce moisture loss after bathing.

Check Availability & Rates
PRIncludes affiliate links
Kusatsuonsen Tenojiya Sulphur Spring
Sulphur SpringAcidic SpringChloride SpringSulphate SpringInfo pending
Kusatsuonsen Tenojiya
草津温泉 ての字屋
Gunma Kusatsu· 宝泉の湯1
The Rock-Born Treasure Spring

Housen-no-Yu, a precious spring at Kusatsu Onsen, one of Japan's three most famous hot springs, has naturally gushed from bedrock for approximately 1200 years. Distinct from major sources like Yubatake and Bandaiko, this rare water gently envelops the skin with its sulfurous aroma. Its crisp quality offers a sensation of purifying both mind and body. After bathing, your skin will feel wonderfully silky, and the restorative warmth from deep within will invite deep relaxation, supporting overall rejuvenation. It is highly recommended for those seeking to escape daily life and reset themselves with a truly special hot spring experience.

Onsen RyokanRoom with Open-air Bath
StimulationBactericidalSkin BeautyHeat RetentionRelaxation
pHStrongly Acidic2
0714
TEMP45
0℃50℃100℃
KEY MINERALS
43.3 mg/kg

Strong astringent action that tightens skin. A key component of acidic springs, suited to oily or acne-prone skin.

The source of the distinctive sulfur smell. Dilates blood vessels via skin and inhalation to strongly boost circulation.

8.4 mg/kg

Mild antibacterial action keeps the skin clean. Trace transdermal absorption supports tooth and bone health.

Check Availability & Rates
PRIncludes affiliate links
Kamenoihoteru Kusatsurizoto Acidic Spring
Acidic SpringChloride SpringSulphate SpringInfo pending
Kamenoihoteru Kusatsurizoto
草津温泉ホテルリゾート
Gunma Kusatsu· 万代鉱Kusatsu Onsen
Scalding Strong Acidic Spring

The Mandaiko source, originating from traces of past mining development, is deeply intertwined with Kusatsu Onsen's unique yumomi culture and its long history of toji (therapeutic bathing). Its highly acidic waters, among Japan's most potent, deliver a distinctive tingling sensation, awakening both mind and body and offering a sense of rejuvenation. The high-temperature blessings penetrate deep into the core, leaving you with a surprisingly light and refreshed feeling after your bath. We invite those seeking a genuine toji experience, a true escape from daily life to restore their mind and body, to discover the profound power of this spring.

Onsen Ryokan
StimulationBactericidalSkin BeautyHeat RetentionRelaxation
pHStrongly Acidic1.75
0714
TEMP94.6
0℃50℃100℃
KEY MINERALS
43.2 mg/kg

Strong astringent action that tightens skin. A key component of acidic springs, suited to oily or acne-prone skin.

25.1 mg/kg

Mild antibacterial action keeps the skin clean. Trace transdermal absorption supports tooth and bone health.

A natural moisturizer also used in skincare lotions. Forms a thin veil on the skin to reduce moisture loss after bathing.

Check Availability & Rates
PRIncludes affiliate links
Kusatsuonsen Bouun Acidic Spring
Acidic SpringChloride SpringSulphate SpringVerified
Kusatsuonsen Bouun
望雲
Gunma Kusatsu· 万代鉱1Kusatsu Onsen
Scalding Strong Acidic Spring

The Mandaiko source, originating from traces of past mining development, is deeply intertwined with Kusatsu Onsen's unique yumomi culture and its long history of toji (therapeutic bathing). Its highly acidic waters, among Japan's most potent, deliver a distinctive tingling sensation, awakening both mind and body and offering a sense of rejuvenation. The high-temperature blessings penetrate deep into the core, leaving you with a surprisingly light and refreshed feeling after your bath. We invite those seeking a genuine toji experience, a true escape from daily life to restore their mind and body, to discover the profound power of this spring.

Onsen Ryokan
StimulationBactericidalSkin BeautyHeat RetentionRelaxation
pHStrongly Acidic1.75
0714
TEMP94.6
0℃50℃100℃
KEY MINERALS
43.2 mg/kg

Strong astringent action that tightens skin. A key component of acidic springs, suited to oily or acne-prone skin.

25.1 mg/kg

Mild antibacterial action keeps the skin clean. Trace transdermal absorption supports tooth and bone health.

A natural moisturizer also used in skincare lotions. Forms a thin veil on the skin to reduce moisture loss after bathing.

Check Availability & Rates
PRIncludes affiliate links
Noboribetsu Onsen Chloride Spring
Chloride SpringFerruginous SpringAcidic SpringSulphur SpringSulphate SpringInfo pending
Noboribetsu Onsen
ホテルまほろば
Hokkaido Noboribetsu· 登別温泉5号泉3Noboribetsu Onsen
Earth's Bounty Salt Waters

Originating from the dramatic Jigokudani (Hell Valley), the potent waters of Noboribetsu Onsen, a renowned hot spring resort in Hokkaido, have long welcomed those seeking therapeutic benefits. This powerful spring gently envelops the skin, delivering restorative warmth that penetrates deep into the body's core. The comforting heat lingers long after bathing, promoting deep relaxation and offering respite from the stresses of daily life. It is highly recommended for individuals desiring an authentic balneotherapy experience in Japan's northern frontier.

Onsen RyokanRoom with Open-air Bath
StimulationBactericidalSkin BeautyHeat RetentionRelaxation
pHNeutral6.7
0714
TEMP94.9
0℃50℃100℃
KEY MINERALS

Undissociated boric acid with antibacterial action that keeps the skin surface clean.

A natural moisturizer also used in skincare lotions. Forms a thin veil on the skin to reduce moisture loss after bathing.

4894 mg/kg

Boosts after-bath warmth and warms the body from the core.

Check Availability & Rates
PRIncludes affiliate links
Tajimayaryokan Sulphur Spring
Sulphur SpringAcidic SpringChloride SpringSulphate SpringInfo pending
Tajimayaryokan
草津温泉 田島屋旅館
Gunma Kusatsu· 湯畑源泉Kusatsu Onsen
The Cure-All Spring

The Yubatake source, naturally gushing from Kusatsu Onsen's iconic Yubatake (Kusatsu's central hot-water field), holds a distinguished history. During the Edo period, it was ranked as the highest-ranking Ozeki in the Onsen Banzuke, recognized alongside the Shirahata source as one of Kusatsu's two major hot springs. Its powerful, pH2 water, permeated with a sulfurous aroma, imparts a refreshing, tightening sensation upon the skin. A soak in this historic, renowned hot spring cleanses the body and mind, offering deep relaxation and rejuvenation from daily fatigue. It is a must-visit for those seeking to feel the energy of a historic hot spring and desire a complete refresh.

Onsen Ryokan
StimulationBactericidalSkin BeautyHeat RetentionRelaxation
pHStrongly Acidic2
0714
TEMP52.3
0℃50℃100℃
KEY MINERALS
49.1 mg/kg

Strong astringent action that tightens skin. A key component of acidic springs, suited to oily or acne-prone skin.

The source of the distinctive sulfur smell. Dilates blood vessels via skin and inhalation to strongly boost circulation.

10.1 mg/kg

Mild antibacterial action keeps the skin clean. Trace transdermal absorption supports tooth and bone health.

Check Availability & Rates
PRIncludes affiliate links
Noboribetsu Onsen Acidic Spring
Acidic SpringFerruginous SpringSulphate SpringChloride SpringCarbonated SpringSulphur SpringSimple SpringVerified
Noboribetsu Onsen
第一滝本館大浴場
Hokkaido Noboribetsu· 1号甲泉2Noboribetsu Onsen
Blessings of the Earth, Powerful Acidic Spring

This is one of the most well-known sources in Noboribetsu, a leading onsen destination in Hokkaido. It continuously flows at a high temperature of 96.5°C, embodying the raw power of the earth. The highly acidic water, with a pH of 2.2, provides a tingling sensation on the skin and a refreshing feeling after bathing. Its rich iron and sulfate content offers a powerful bathing experience that feels as if it's awakening both mind and body. It's a spring for those who wish to reset from daily fatigue, gain new vitality, and feel nature's energy throughout their entire being.

Onsen RyokanRoom with Open-air BathTattoo OK (public bath)
StimulationBactericidalSkin BeautyHeat RetentionRelaxation
pHStrongly Acidic2.2
0714
TEMP96.5
0℃50℃100℃
KEY MINERALS

Undissociated boric acid with antibacterial action that keeps the skin surface clean.

16.9 mg/kg

Strong astringent action that tightens skin. A key component of acidic springs, suited to oily or acne-prone skin.

A natural moisturizer also used in skincare lotions. Forms a thin veil on the skin to reduce moisture loss after bathing.

Check Availability & Rates
PRIncludes affiliate links
Oyado Konoha Sulphur Spring
Sulphur SpringAcidic SpringChloride SpringSulphate SpringInfo pending
Oyado Konoha
木の葉
Gunma Kusatsu· わたの湯1Kusatsu Onsen
The Cotton-Wrapped Spring

This rare, naturally gushing source emerges from beneath 'Gensenkaku,' nestled beside Kusatsu Onsen's iconic Yubatake (Kusatsu's central hot-water field). Despite its strong acidity, its waters offer a remarkably soft bathing sensation, akin to being enveloped in silk floss. The milky-white waters, renowned for having Kusatsu's finest 'yunohana' (hot spring minerals), gently embrace the skin, contributing to silky skin and providing a restorative warmth that lingers deep within the body. Known as a 'phantom spring' for its history of disappearing once during the Taisho era, it now offers a profound escape from daily life, inviting deep relaxation and rejuvenation.

Onsen RyokanPrivate Rental Bath
StimulationBactericidalSkin BeautyHeat RetentionRelaxation
pHStrongly Acidic2.1
0714
TEMP50.2
0℃50℃100℃
KEY MINERALS
44.3 mg/kg

Strong astringent action that tightens skin. A key component of acidic springs, suited to oily or acne-prone skin.

The source of the distinctive sulfur smell. Dilates blood vessels via skin and inhalation to strongly boost circulation.

9.6 mg/kg

Mild antibacterial action keeps the skin clean. Trace transdermal absorption supports tooth and bone health.

Check Availability & Rates
PRIncludes affiliate links
Sengokuharaonsen Senkyourou Acidic Spring
Acidic SpringSulphate SpringChloride SpringVerified
Sengokuharaonsen Senkyourou
仙郷楼
Kanagawa Hakone· 大涌谷温泉 蒸気造成混合泉
Owakudani's Earthly Pulse

Originating from the fumaroles of Owakudani, born from the eruption of Hakone volcano approximately 3,000 years ago, this artificially developed hot spring began to be supplied to Sengokuhara and Gora by Hakone Onsen Kyokyu Co., Ltd. in Showa 5 (1930). Its renowned milky white waters, blended with naturally gushing spring water, offer a pleasant sensation that tightens the skin and a powerful restorative warmth that penetrates deep into the body's core. After bathing, you'll feel surprisingly refreshed and light. It's a perfect companion when you seek to feel the Earth's energy and achieve deep relaxation and rejuvenation for your mind and body.

Onsen RyokanPrivate Rental BathRoom with Open-air Bath
StimulationBactericidalSkin BeautyHeat RetentionRelaxation
pHStrongly Acidic2.1
0714
TEMP60.6
0℃50℃100℃
KEY MINERALS
7.5 mg/kg

Tightens the skin and balances sebum.

A natural moisturizer also used in skincare lotions. Forms a thin veil on the skin to reduce moisture loss after bathing.

14.2 mg/kg

A trace component with gentle antibacterial and anti-inflammatory action.

Check Availability & Rates
PRIncludes affiliate links
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