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Yunoko Onsen Umi to Yuyake

湯の児温泉 海と夕やけゆのこおんせん うみとゆうやけ

Lodging
Yunoko Onsen
Kyushu & Okinawa·Kumamoto
0966-62-6262umitoyuyake.com

Day Use

Yes
12:00–15:00

Day-use bathing occasionally isn't available on days set aside for facility maintenance; check the official site's notice page for exact dates.

¥1,000

Adults 1,000 yen, elementary school age and younger 500 yen; a white towel can be bought separately for 150 yen.

Bathing & Water

Outdoor BathYes

Open-air outdoor bath

Indoor BathYes

Enclosed indoor bathing area

SaunaYes

Dry heat sauna room

Standard sauna in the main bath (men's & women's), plus a separate paid, reservable wood-fired tent sauna (UMIYU SAUNA).

Cold BathYes

Cold water plunge bath, typically used after sauna

OnsenYes

Uses natural hot spring water

Capabilities

Private BathNo

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

Policies & Services

TattooNo

Allows entry with visible tattoos

Stated in the terms for the add-on private tent sauna (UMIYU SAUNA), phrased broadly enough to suggest a facility-wide policy, but not separately confirmed for the main indoor/outdoor bath.

KidsYes

Welcomes children and families

Extensive family amenities; the separate paid wood-fired tent sauna restricts children age 12 and under.

DiningYes

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

Day-trip (no bathing) meal use is by reservation and currently limited to weekends only.

TowelsYes

Towels available to rent or borrow

ParkingYes

On-site or nearby parking available

Water treatment

Treated and recirculated
from Article 18 disclosure
  • Added water
    Yes
  • Reheated
    No
  • Recirculated
    No
  • Disinfected
    No
  • Bath additives
    No

源泉No.1 及び 源泉No.2 の混合泉

Spring No.1 and No.2 (blended)

Operated by · 湯の児 海と夕やけ

Mixed source

曹
Bicarbonate
+ Chloride
Color
colorless and clear
Taste
slightly salty
Odor
faint hydrogen sulfide

Sodium Bicarbonate-Chloride spring

Hot source · 51°CHigh silica
Composition fingerprint2.1 g/kg dissolved · Hypotonic
Na⁺80
Ca²⁺12
HCO₃⁻65
Cl⁻34
◀ CationsAnions ▶
Sodium Na⁺
salt's cation — pairs with chloride to make the water salty.
Bicarbonate HCO₃⁻
"soda" — softens skin, leaves it smooth.
Known good for
  • Smooth skindry, rough skin
  • Aches & jointsstiff shoulders
  • Warmingcold sensitivity

A blended source drawing from wells No.1 and No.2, a sodium-led bicarbonate water with a chloride sub-type — the classic sodium bicarbonate (jūsō-sen) style finished with a salty edge. Both wells emerge in the low-50s °C and are diluted only when the season pushes them too hot, so the bath stays weakly alkaline and soft on the skin, sitting squarely in Japan's beauty-water family. Metasilicic acid at 62 mg/kg leaves a thin silica film that smooths the skin, while a faint hydrogen sulfide note trails a mildly salty taste.

Sampled at mixing tank·Analyzed Jan 28, 2022·株式会社 三計テクノス

Explore the water

Views

Sea

Programs

About

Yunoko Onsen sits in a quiet bay on the Shiranui Sea in Minamata, and the hotel's baths look out toward the Amakusa islands across the water. The large indoor bath and a compact open-air bath one floor up share the same spring water, kept flowing fresh, slightly alkaline and faintly salty, smooth on the skin. Both the men's and women's sides add a dry sauna and cold plunge, and a separate paid wood-fired tent sauna can be booked for a private session. Local legend puts the spring at close to 1,900 years old, said to have been found when an injured sea turtle was seen healing itself in the water, which is why the indoor bath still carries the turtle's name. The open-air bath's sunset view across to Amakusa, part of what gives the hotel its name, is well known locally.

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SM
Sergey M
1 year ago

381. Yunoko Umi to Yuyake, Minamata, Kumamoto Visited for higaeri for 500 yen. Higaeri listed as 14:00 to 18:00. They issue Toreco cards for this onsen. Photos from the internet roughly match — I was there in daylight but everything looks very similar. Indoor bath with clear water, temperature around 40. Breathing is good. Before the stairs from the first floor indoor bath to the second floor outdoor bath, there's a box with disposable shorts (but no large sizes), listed as mandatory since if you stand up fully in the outdoor bath you'll be visible from the park. Though if you slide into the water from the edge directly, everything will be fine. Small outdoor bath with a nice view, clear water, temperature around 43. The hassle with the disposable shorts is a bit off-putting, but otherwise it's decent.

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Last updated July 14, 2026