Onsen OniOnsen Oni

Search Onsen Oni

Search onsen, areas, prefectures and pages.

Kaiun-no-yu

盛南温泉 開運の湯もりみなみおんせん かいうんのゆ

Morioka day-use onsen complex with carbonated and radon baths

Bathing Complex
Tohoku·Iwate

Day Use

Yes
10:00–00:00
¥750

Adult ¥750; child ¥400; infant (2 and under) free. Early morning (Sat/Sun/holidays 6:30–10:00): adult ¥600, child ¥350. Ganbanyoku + pulgama add-on: +¥450. Sauna included in admission. Towel rental set ¥220. Cash only.

Bathing & Water

Natural onsen water

Uses natural hot spring water

Outdoor BathYes

Open-air outdoor bath

Indoor BathYes

Enclosed indoor bathing area

SaunaYes

Sauna room of any kind

Cold BathYes

Cold water plunge bath, typically used after sauna

Bathing Arrangements

Private BathYes

A private bath you can reserve for yourself or your group

Mixed BathingNo

Shared bathing area for all genders

Policies & Services

TattooNo

Allows entry with visible tattoos

KidsWith Conditions

Welcomes children and families

Children 7 and over must use gender-separated baths.

DiningYes

A restaurant or dining room open to visitors, not only meals for overnight guests

WashingYes

Shower, wash stations, soap and shampoo provided

TowelsYes

Towels to rent or borrow at the desk

Rest AreaYes

Relaxation space for after bathing

ParkingYes

On-site or nearby parking available

盛南温泉(開運の湯)

Seinan Onsen (Kaiun-no-yu)
湯
Simple
+ 弱放射能泉

Sodium Chloride-Carbonate spring

High radonStrongly alkaline
Composition fingerprint0.2 g/kg dissolved · Hypotonic
Na⁺96
Cl⁻45
CO₃²⁻35
◀ CationsAnions ▶
Sodium Na⁺
salt's cation — pairs with chloride to make the water salty.
Chloride Cl⁻
table-salt anion — coats the skin and holds heat in.
Known good for
  • Aches & jointsstiff shoulders
  • Smooth skindry, rough skin
  • Recoveryfatigue, stress

A simple weak-radon spring rising in a residential pocket of Morioka. Strongly alkaline at pH 9.9, it has the slippery feel of the Japanese beauty-water family. Light overall mineralization (234 mg/kg dissolved solids) is offset by a notable radon load — 121 Bq/kg, well into the hormesis-tradition range. The wellhead runs at 31 C, so the bath is reheated for soaking.

Sampled at wellhead·Analyzed May 25, 2017·一般社団法人 岩手県薬剤師会·Cert no. 岩手県第1号

Explore the water

Highlights

Ganbanyoku

About

Seinan Onsen Kaiun no Yu (盛南温泉 開運の湯, "good-luck bath") is a day-use onsen complex in Morioka drawing natural spring water from underground. The bathing floor has indoor and outdoor pools, a carbonated bath, a radon bath, a sauna with cold plunge, and a private reserved bath (kashikiri, 貸切風呂) for small groups. An add-on ganbanyoku (岩盤浴, heated stone bed) and Korean-style pulgama steam room are available for an extra fee. A restaurant on the premises serves lunch and dinner.

Loading map…

2.0

1 review

5
0
4
0
3
0
2
1
1
0
SM
Sergey M
2 years ago· edited

212. Kaiun-no-yu, Morioka An old onsen complex, 4 minutes by taxi from Morioka Station. With a towel set, it costs 970 yen. There is a massage service, a diner, and a small shop. There is a private bath for 2200 yen and a stone bath, but I did not use them. There were quite a lot of people for such a small place at 11 p.m. on Sunday, but nobody bothered anyone. 1. Indoor area. It is comfortable to breathe inside, but there is a chlorine smell. 1.1. A smaller rectangular bath with clear onsen water, around 40 degrees. The water is clear, with a noticeable chlorine smell. 1.2. A large rectangular bath with tap water enriched with something that is hard to explain in plain language, 高濃度 炭酸イオン泉. The water is clear, it smells like a mix of chlorine and some other smell, and the temperature is 36 to 38 degrees. 1.3. A cold-water bath. 1.4. A sauna. 1.5. In the passage between the indoor and outdoor areas, there is a small square bath with clear warm water. It looks stagnant, and I did not understand its purpose. 2. Outdoor area. 2.1. A large stone bath with onsen water. A small bridge runs across the bath. The water is clear, the temperature is 36 to 38 degrees, and there is a chlorine smell, but not as noticeable as in the indoor bath. On one side of the bath there is a shallow area, about one quarter of the size of this whole bath. 2.2. A small stone bath on a raised level. Judging from the diagram, the water is tap water, clear, with a chlorine smell. The temperature is 36 to 38 degrees. A mixed onsen. If you have very little time and need an onsen near the station, and the chlorine does not bother you, then maybe it is fine. 03.11.2024

1
2
3
4
5
6
7
8

Last updated October 12, 2026