Japan's hot springs

Every onsen in JapanMapped in full detail

The most advanced map of Japan's hot springs. Follow the stamp tours and meguri, earn badges, and keep a personal onsen journal. Built by bathers, every place checked by hand.

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The map

The most advanced onsen map in Japan

Browse by onsenchi (温泉地), the hot-spring areas, or filter by anything: outdoor baths, tattoo policy, day-use hours, kashikiri, and a whole vocabulary of rarer features no other map covers. Tap any onsen for photos, ratings, and the details that decide a visit.

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A few of the rarer filters

Onsen Passport

Your passport, your journal, your map

Every soak, review, and finished meguri lands in your profile: a personal map of where you've bathed, a journal of your visits, and a wall of badges you can share. Collect them all.

Badges to collect

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Pilgrimages

Stamp tours and meguri

Japan's stamp rallies, sotoyu-meguri, and onsen-do, gathered in one catalog and each one mapped and trackable. Walk a region end to end and earn a badge that means something.

All programs

Chemistry

Know the water, and what it's good for

For most onsens in our catalog, you'll find the full water chemistry: the spring type, pH, temperature, tonicity, dominant ions, color, taste and smell, and the conditions Japanese medical authorities recognize the water for. Everything an operator must publish on their water-analysis certificate (bunsekisho, 温泉分析書), laid out so you can actually read it.

見本源泉第1号

黄

Sulfur

+ Acidic · Sulfate

Color: Slightly cloudy yellow
Taste: Strong sour
Odor: Sulfur

Hydrogen-Aluminum Sulfate-Chloride spring

pH 2.1AcidicHot source · 48°CUltra-acidicSulfur-rich

Composition fingerprint2.4 g/kg dissolved · Hypotonic

H⁺52

Al³⁺28

Ca²⁺12

SO₄²⁻60

Cl⁻25

◀ CationsAnions ▶

Hydrogen H⁺: makes the water acidic — sharp and bactericidal.
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

An acidic sulfur–sulfate source — hot at the wellhead, with a strong sour taste and the unmistakable sulfur note. Drains the skin of oils; recommended after a long day.

Community

Built by onsen lovers, for onsen lovers

Reviews, ratings, and photos from the bathhouse. Visit logs that build up your own onsen journal. Every place is checked by hand before it lands.

Reviews & ratings

Five-star ratings and written notes from people who actually went.

Photos from the bath

From lobby signs to the bath itself, uploaded by visitors.

Curated by hand

Every submission and edit checked by a moderator before it goes live.

Hand-picked

A few we keep coming back to

Real onsen, real photos. Tap any card to open the page.

Hotel Mount Fuji

Yamanashi

Sansuikan Kawa Yu Midori Ya

Wakayama

Tateshina Shinyu Onsen

Nagano

Nanki Shirahama Hamachidori No Yu Kaishū

Wakayama

Ikoi Ryokan

Kumamoto

Hakone Kowakien Ten-yu

Kanagawa

Yadoyunosato

Nara

Yumotokan

Shizuoka

Taisenkaku

Mie

Nakanoshima

Wakayama