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Niji no yu

虹の湯二色の浜店にじのゆふたいろのはまてん

Day-use super-sento near Kaizuka beach with onsen baths and sauna

Bathing Complex
Kansai·Osaka

Day Use

Yes
10:00–00:00

Last entry is at 23:15 (close at 24:00). The bathhouse stays open through the New Year holidays with no closures.

¥800

Reviews mention an adult price of about 950 yen on weekends and holidays, and around 750 yen on weekdays with a coupon; the regular weekday rate isn't confirmed elsewhere.

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

Policies & Services

KidsWith Conditions

Welcomes children and families

Children of elementary-school age or younger must be accompanied by an adult; unaccompanied use is refused.

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

A rest area exists but reviewers describe it as small with limited seating.

虹の湯温泉 二色の浜店

Niji-no-yu Onsen Nishiki-no-hama

Operated by · 株式会社ALLURE

湯
Simple
Color
faintly yellow and clear
Taste
almost tasteless
Odor
odorless

Sodium-Calcium Bicarbonate spring

pH 7.4NeutralHigh silica
Composition fingerprint0.3 g/kg dissolved · Hypotonic
Na⁺61
Ca²⁺29
HCO₃⁻93
◀ 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
  • Recoveryfatigue, stress

A lightly mineralized simple thermal spring. The wellhead measures 29.7 °C, putting it in the low-temperature class — the bath water is reheated before serving. Neutral pH (7.4) and a faint yellow tint give a gentle, unassuming character, while a meaningful 60.8 mg/kg of metasilicic acid leaves the skin slightly smoother than the modest mineralization would suggest.

Sampled at wellhead·Analyzed May 29, 2024·株式会社総合水研究所·Cert no. SP240010

Explore the water

Highlights

Electric Bath
Jet Bath
Steam Sauna

About

A day-use super-sento (part of the Niji no Yu chain) near the coast in Kaizuka, with natural onsen water running through an indoor jet bath, electric bath, and cold plunge, plus an outdoor rotenburo. A separate outdoor kamaburo works like a steam sauna. Reviewers say every bath does its job well, and the restaurant and rest area, stocked with manga, make for an easy stop after soaking.

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1 review

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Sergey M
1 year ago· edited

323. Niji no yu, Osaka ★ A super sento with onsen water, 30 minutes from Kansai Airport for 800-900. Opening hours are listed as 10:00 to 24:00. They stamp the Kansai 41 Super Sento 24/25 rally. There is a diner, massage, a barber shop, and massage chairs. 1. Outdoor area. 1.1. A pleasant round rotenburo with rocks. The water is a slightly cloudy white-brown, temperature 40. 1.2. Three barrels with water like in the rotenburo. 1.3. A rectangular herbal bath, it used to be ginger, with a TV, the water is clear yellowish. 1.4. A lounging area. 1.5. Steam sauna. 2. Indoor area. 2.1. A bath with clear yellowish water, also herbal, apparently an event bath, temperature 40. 2.2. Three jet reclining baths. 2.3. Four jet sitting/standing baths. 2.4. Three electric baths. 2.5. Sauna. 2.6. Cold bath. A good place, I would consider it together with a visit to Kansai Airport. 03.01.2025

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Last updated October 13, 2026