Gunma · Ikaho Onsen
Ikaho Open-air Bath
伊香保露天風呂
A public open-air bath built right at Ikaho's spring source, above the stone-step street and Kajika Bridge. Nothing but bamboo-fenced outdoor pools where the rusty-brown 'golden water' flows straight from the source. Pair it with the bridge in autumn.
- Price (adult)
- ¥600
- Hours
- 09:00–18:00 (from 10:00 Oct–Mar; entry until 30 min before closing)
- Closed
- 1st & 3rd Thursdays (open if a holiday)
- Access
- 20 min walk from Ikaho Onsen bus terminal
- Water type
- Sulfate spring
- Tattoos
- Ask ahead
- Admission
- Adults ¥600 / children ¥300. Infants under 1 not admitted. Cash
- Water
- Right beside the source of Ikaho’s “Kogane-no-yu” (golden water): calcium-sodium-bicarbonate-sulfate spring that turns rust-brown on contact with air. Free-flowing, one hot and one warm tub. Long known as a fertility bath
- Facilities
- Open-air baths only, separate for men and women. No showers, washing area or soap — soak only. Simple changing room with lockers. Municipal facility
- Nearby
- Free drinking fountain (iron taste), a statue of Dr Baelz who promoted spa therapy in the Meiji era, and a viewing spot for the source outlet are just outside; the Kajika Bridge autumn-leaf spot is 5 min away
- Phone
- 0279-72-2488
- Official site
- www.city.shibukawa.lg.jp/kankou/000357/000361/p000219.html ↗
- Open in Google Maps
- Google Maps ↗
Essentials
Stay in this onsen town
Compare and book stays in Ikaho Onsen. Day bathing itself needs no booking.
Opens partner booking site (affiliate)
Why go
- Rusty 'golden water' right at the source
- Open-air only, bamboo-fenced
- Combine with Kajika Bridge in autumn
Soaking at the very source of Ikaho’s golden water
Ikaho has two waters: the old iron-rich “Kogane-no-yu” that turns golden-brown, and the newer clear “Shirogane-no-yu”. The municipal Ikaho Rotenburo sits right beside the source of the golden water, past the top of the 365 stone steps, beyond Ikaho Shrine and up along the stream. Fresh spring water pours straight in, making this the “strongest” golden bath in town, and its charm is its simplicity — just two open-air tubs, hot and warm, ringed by cedars. Outside are a drinking fountain and a statue of Dr Erwin Baelz, the German physician who promoted Ikaho as a spa resort in the Meiji era.
Tips & cautions
- No washing area, showers or soap — wash at your inn first or simply soak. Bring a towel.
- Iron-rich water stains white towels brown; there is no rinse shower.
- Opens 10:00 in Oct–Mar; entry until 30 min before closing. Closed 1st & 3rd Thursdays (open if a holiday).
- 15–20 min uphill from the stone steps; by car, 5 min walk from the free Kajika-bashi car park (~20 spaces).
- No infants under 1. The changing room is cold in winter.
- Very crowded during the early-November foliage season around Kajika Bridge.
Getting there
Kan-etsu Kotsu bus ~25 min from JR Shibukawa Station to the “Ikaho Onsen” terminus, then ~20 min up through the stone-step street (Ikaho 581). By car ~12 km from Shibukawa-Ikaho IC; 5 min walk from the free Kajika-bashi car park.
Before you go
- No official tattoo policy is published — ask at reception.
- As a communal bath there is no soap or shampoo — bring your own or buy at the shop.
- Payment is usually by ticket machine in cash — bring coins.
- Last entry is 30–60 minutes before closing.
Features
Price
Mood & scenery
Amenities
✔ Verified operating: 2026-09 渋川市公式(2026-05)
Prices and hours change. Check official sources before visiting.
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