Ryokan Nanjoen

黒川温泉旅館南城苑くろかわおんせんりょかんなんじょうえん

Lodging
Kyushu & Okinawa·Kumamoto

Day Use

Yes
08:30–21:00

There may be days off

Bathing & Water

Outdoor BathYes

Open-air outdoor bath

Indoor BathYes

Enclosed indoor bathing area

OnsenYes

Uses natural hot spring water

Capabilities

Private BathYes

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

Room OnsenYes

Private onsen bath in guest rooms, for overnight guests only

旅館南城苑

Ryokan Nanjoen Source

Operated by · 旅館 南城苑

Simple
Color
nearly colorless and clear
Taste
faintly acidic with a very slight metallic note
Odor
faint hydrogen sulfide with a very slight metallic note

Sodium Sulfate-Chloride spring

Hot source · 55°CHigh silica
Composition fingerprint0.6 g/kg dissolved · Hypotonic
Na⁺47
Ca²⁺19
SO₄²⁻72
Cl⁻27
CationsAnions
Sodium Na⁺
salt's cation — pairs with chloride to make the water salty.
Sulfate SO₄²⁻
"gypsum / Glauber's salt" — vessels and wound healing.
Known good for
  • Aches & jointsstiff shoulders
  • Smooth skindry, rough skin
  • Recoveryfatigue, stress

A simple thermal spring on the acidic side of weakly acidic (pH 3.7), emerging at 55 °C and so classed as a hot source. The water is nearly colorless and clear at the wellhead, carrying a faint rotten-egg note of hydrogen sulfide and a trace metallic edge in both smell and taste. Total dissolved solids sit on the light side at 568.9 mg/kg, but 169.9 mg/kg of metasilicic acid lends a noticeably smooth feel against the skin.

Analyzed Sep 6, 2022·株式会社三井テクノス

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3.0

2 reviews

from 1 reviewer

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SM
Sergey M
1 year ago· edited

407. Ryokan Nanjoen, Kurokawa Onsen (pt.2 - second set of baths) ★ The second set of outdoor baths for men and women. A partial view of houses and trees through the fence. There is an onsen for the face in the changing room. Two rectangular baths. The water is clear, slightly cloudy with a greenish tint. The temperature is 43.5-44°C in the upper bath and 42°C in the lower bath. There is also some kind of drain bath with cold water. Although the onsens are not stone-made or scenic, having this option expands the variety in the village overall. 14.01.2025

SM
Sergey M
1 year ago· edited

407. Ryokan Nanjoen, Kurokawa Onsen (pt.1 - first set of baths) ★ Visited on a day trip, located in the building next to the tourist center. Usually, day trips are available from 8:30 to 21:00, rarely closed during the week. Included in the Tegata Kurokawa pass. For day trips, only the outdoor baths are accessible - they are different and alternate daily by gender. There is merchandise with the anime mascot. The ryokan has its own branded towels. The staff are very pleasant and friendly. There is a private bath (did not use). The first set of outdoor baths by gender. The view is of houses and trees. Three rectangular baths on different levels: one standing bath, one regular bath, and a shallow lower bath. The water is clear, slightly cloudy with a greenish tint. Temperature is 41°C in the upper baths and 37.5°C in the lower bath. 13.01.2025

Onsen Oni

Last updated June 19, 2026