Unzen Onsen Seiunso

雲仙温泉青雲荘うんぜんおんせんせいうんそう

Lodging

Kojigoku Onsen

Kyushu & Okinawa·Nagasaki

0957-73-3273 seiunso.jp

Contact form

Day Use

Yes

Bathing & Water

Natural onsen water

Uses natural hot spring water

Outdoor BathYes

Open-air outdoor bath

Indoor BathYes

Enclosed indoor bathing area

Capabilities

Private BathYes

Private bath available for day-use visitors or hotel guests to reserve

Room OnsenNo

Private onsen bath in guest rooms, for overnight guests only

Mixed BathingNo

Shared bathing area for all genders

Standard gender-separated bathing; no mixed-bathing offering mentioned anywhere across the site, Google reviews or aggregator listings.

Policies & Services

DiningYes

Restaurant or dining open to visitors (not just hotel meal plans)

Confirmed usable by a day-use (日帰り) visitor, not just overnight guests.

WashingYes

Shower, wash stations, soap and shampoo provided

TowelsYes

Towels available to rent or borrow

Rest AreaYes

Relaxation space for after bathing

ParkingYes

On-site or nearby parking available

Water treatment

Not disclosed

from Article 18 disclosure

Added water
Not disclosed
Reheated
Not disclosed
Recirculated
Not disclosed
Disinfected
Not disclosed
Bath additives
Not disclosed

雲仙温泉（小地獄）

Unzen Onsen (Kojigoku)

Operated by · 株式会社青雲荘

黄

Sulfur

Color: milky white, slightly turbid
Taste: slightly acidic
Odor: faint hydrogen sulfide

Calcium-Sodium Sulfate spring

pH 3.9Weakly acidicHot source · 64°CHigh silicaSulfur-rich

Composition fingerprint0.2 g/kg dissolved · Hypotonic

Ca²⁺26

Na⁺22

NH₄⁺17

SO₄²⁻90

◀ CationsAnions ▶

Calcium Ca²⁺: settling and calming; can leave a white mineral bloom.
Sulfate SO₄²⁻: "gypsum / Glauber's salt" — vessels and wound healing.

Known good for

Skin conditionsatopic skin, eczema
Circulationtired legs
Aches & jointsstiff shoulders

Sensitive-skin cautionbroken or dry skin

A simple sulfur spring of the hydrogen-sulfide type rising at Kojigoku in Unzen. At the source the water is milky and slightly turbid, with a faintly acidic taste and the characteristic rotten-egg note of H₂S. It is a weakly acidic, hot spring carrying 80.5 mg/kg of metasilicic acid, which leaves the skin smooth. The posted indications cover neuralgia, muscle and joint pain, sensitivity to cold and recovery from fatigue. Because the source temperature is high, fresh water may be added to cool it.

Sampled at wellhead·Analyzed Oct 29, 2009·財団法人佐賀県環境科学検査協会·Cert no. 佐環検温第24号

Explore the water

About

A ryokan in Unzen with its own hot-spring source, a rarity in this area. The outdoor bath sits within earshot of a mountain stream, and the indoor bath is a high-ceilinged room filled with milky white sulfur water. There's also a private (kashikiri) bath for families with small children. Guest rooms don't have their own tub, so all bathing happens in these shared baths. The inn sits a little apart from Unzen's main sightseeing streets, in a quiet, tree-covered spot.

Loading map…

Reserve or check availability on a booking site.

Rakuten TravelStay JalanStay YukoyukoStay

Sergey M

2 years ago

Unzen Onsen Seiunso, Unzen (Pt.2 - private baths) For day-use, you can get private baths for an extra fee (2,500 yen for 50 min, choice of one of two). Inside they're different - the first is simpler, the second is more stylish and larger. But the water in the second one is really hot, for those who like it that way. Otherwise, the water seems similar. Breathing is comfortable in both.

Sergey M

2 years ago

Unzen Onsen Seiunso, Unzen (Pt.1 - indoor and outdoor bath) A relatively modern ryokan, the bath entrance is on the first floor. For day-use until 18:00, all baths are available - indoor plus exit to a small outdoor bath, and a separate outdoor bath. Cost with large towel rental is 1,250 yen for everything. The water is milky blue, not much smell, good temperature, comfortable breathing. In the indoor bath there are several grooves for your body and head where you can lie down comfortably. Through the indoor bath you can exit to a small outdoor area with two small single-person baths. The outdoor bath water seemed similar, it's on a kind of large "balcony." Highly recommend.