Kusatsuonsen Ichii
Image: Agoda
PR · Agoda

Kusatsuonsen Ichii

ホテル一井
Info pending

Gunma Kusatsu

群馬県 草津町

Onsen RyokanFree-Flowing Onsen

AT A GLANCE

Kusatsuonsen Ichii is an acidic spring, chloride spring, and sulfate spring (pH 1.7, strongly acidic). Naturally flowing (no recycling or dilution). Contains ≥50 mg/kg of metasilicic acid, certified as a beauty spring. Per Japan's Ministry of the Environment guidelines, indicated for atopic dermatitis and psoriasis.

SOURCES
♨Bandaiko
万代鉱
酸性水素一硫酸塩・塩化物温泉
酸
Acidic Spring
塩
Chloride Spring
硫塩
Sulphate SpringpH 1.794.6℃掘削自噴
See effects, components & details
♨Shirahata Spring
白旗源泉
Acidic sulfurous aluminum sulfate chloride spring (hydrogen sulfide type) (hypotonic acidic hot spring)
硫
Sulphur Spring
酸
Acidic Spring
塩
Chloride Spring
硫塩
Sulphate SpringpH 251.9℃Natural sp…
See effects, components & details

If a source spring listed for this facility looks incorrect, please contact us.

How Long to Stay (Toji)
Start with 2 nights / 3 days

Japan’s Ministry of the Environment notes that even a short stay refreshes you. For a full therapeutic cure, around 2–3 weeks is the guideline.

More on toji length
Stay at this hotel
PR

Kusatsuonsen Ichii

From¥17,600/ person / night (tax incl.)
4.7(3305)

Approx. lowest rate (varies by date & guests)

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Sample caption

Kusatsuonsen Ichii (Kusatsu) Acidic Spring / Chloride Spring / pH 1.7 / 94.6℃ #onsen #kusatsu #acidicspring https://onsen-analysis.com/en/onsen/kusatsuonsen-ichii?utm_source=card&utm_medium=social&utm_campaign=onsen_card

USAGE
Free-Flowing Onsen
Pure spring water — no dilution, no recirculation
HeatedNo
DilutedNo
RecycledNo
FilteredNo
DisinfectedNo
AdditivesNo
▸Note

The temperature, pH and component values shown here are based on the hot spring analysis (source). Actual values in the bath may differ depending on heating, dilution, recycling and filtration. Please check current usage status at the facility.

FACILITY INFO
AI draft (unverified)
Official site
Official siteOpen
Tattoo
No tattoosGuests with tattoos (irezumi) are kindly requested to refrain from using the public baths and open-air baths.
About tattoos and onsen
Hours
Weekdays: 15:00〜10:00
Weekends & holidays: 15:00〜10:00
The men's and women's baths switch daily at 3:00 PM and 5:00 AM. The baths are closed during the day for cleaning and at night for security and accident prevention.
Transit
From JR Agatsuma Line (JR吾妻線) 'Naganohara-Kusatsuguchi Station' (長野原草津口駅), take a local bus for approx. 25 minutes to 'Kusatsu Onsen Bus Terminal' (草津温泉バスターミナル). From the bus terminal, it's about a 3-5 minute walk. Alternatively, shuttle service is available from the bus terminal (reservation required). From Busta Shinjuku (バスタ新宿), take the highway bus 'Joshu Yumeguri-go' (上州ゆめぐり号) to Kusatsu Onsen Bus Terminal (草津温泉バスターミナル) (approx. 247 minutes), then about a 3-minute walk.
Parking
Available. 500 JPY per night per vehicle. Capacity: 100 vehicles. Available hours: 12:00 PM (noon) to 12:00 PM (noon) the next day. Not available for day-use guests. Height limit: 2.8m.
Phone
0279-88-0011
Facilities
RestaurantLoungeBanquet HallPublic BathOpen-air BathShopVending MachineEV Charging Station
House rules
All rooms are non-smoking (smoking areas are located on the 3rd floor front lobby of the main building and the 2nd floor elevator hall of the annex). The public baths and open-air baths operate on a gender-swapping schedule.
Sources
Rakutentravel.yahoo.co.jpOfficialspa.or.jpyukoyuko.netJalanaic.pref.gunma.jpjtb.co.jpweb.mytrip.net
This information may change without notice. Please contact the facility directly for accurate details.
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✨ The descriptions, catch phrases, and translations on this page are generated by AI (Claude). pH, temperature, and component values are OCR-extracted from the official analysis report. Learn more