Ryokan Shirasagi

湯治のできる宿しらさぎとうじのできるやどしらさぎ

Lodging

Kansai·Wakayama

0739-46-0321 tsubaki-shirasagi.jp

Day Use

Yes

11:00–20:00

may be until 14:00

¥600

Bathing & Water

Natural onsen water

Uses natural hot spring water

Outdoor BathNo

Open-air outdoor bath

Indoor BathYes

Enclosed indoor bathing area

Policies & Services

WashingYes

Shower, wash stations, soap and shampoo provided

蓬来湯

Horai-yu

Operated by · (社)共済組合

黄

Sulfur

Color: colorless and clear
Taste: salty
Odor: faint hydrogen sulfide

Sodium Chloride-Carbonate spring

pH 10.1AlkalineSulfur-richStrongly alkaline

Composition fingerprint0.3 g/kg dissolved · Hypotonic

Na⁺97

Cl⁻39

CO₃²⁻28

◀ 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

Skin conditionsatopic skin, eczema
Circulationtired legs
Smooth skindry, rough skin

Sensitive-skin cautionbroken or dry skin

Horai-yu is a strongly alkaline simple sulfur spring (pH 10.1) — sharply slippery on the skin, sitting squarely in the Japanese 'beauty-water' family. At the wellhead the water carries a faint rotten-egg note of H₂S and a mild salty tang. Mineralization is light at 0.284 g/kg, so the character comes from the sulfur fraction (HS-, thiosulfate) and the high pH rather than from bulk solutes. Classified as a low-temperature spring (31.8 °C) heated for bathing.

Sampled at wellhead·Analyzed Dec 18, 1997·和歌山県衛生公害研究センター·Cert no. 第6号-6

Explore the water

Programs

About

A small family-run inn at Tsubaki Onsen (椿温泉), on the coast south of Shirahama, going since 1954 and still built around toji (湯治), the old practice of settling in for days and letting the water do the work. Self-catering toji stays are still possible here, which is rare in Kansai. The bath sits about 60 metres above the sea with the Pacific straight ahead, so you soak through the sunset and, later, the lights of the fishing boats. The water is a simple sulfur spring, smooth and slippery on the skin, never diluted and never recirculated. It leaves the ground at about 32C, so the main tub is heated while the small tsubo-yu (壺湯) pots hold the source as it comes and get a different infusion each day: yuzu, local mandarins, aloe, loquat leaf, seaweed, sometimes coffee. Going back and forth between the hot tub and the cool pots is how people use the place.

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9 months ago

664. Ryokan Shirasagi, Tsubaki, Shirahama, Wakayama ★ Onsen with alkaline water (pH 10.1). Visited for higaeri for 600. Higaeri hours are 11:00-20:00 or 11:00-14:00 (varies by day). They stamp the Wakayama 88 Onsen book. They sell the Wakayama 12 Onsen stamp book. There is a gender rotation for baths. 1. First set of indoor baths by gender. A bit stuffy inside. View through old glass windows to the ocean. 1.1. Main bath with clear water, temperature around 41.5. 1.2. Coffee bath, temperature around 33. 1.3. Mandarin orange bath with clear water, temperature around 36. 1.4. Herbal bath (houttuynia). Clear water with a pale yellowish tint. Temperature around 35. 2. Second set of indoor baths by gender. A bit stuffy inside. View through old glass windows to the ocean. 2.1. Main bath with clear water, temperature around 43. 2.2. Yuzu bath with clear water, temperature around 36. 2.3. Herbal bath (mugwort). Clear water with a faint brown tint. Temperature around 35. Having a coffee bath is a pretty cool touch worth noting. Otherwise these are old hotel baths with an ocean view. 07.11.2025 09.11.2025

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Last updated July 29, 2026