Semboku, Akita / 玉川温泉
Tamagawa Onsen
A mountain hot-spring retreat known for Japan's most acidic spring water (pH 1.2, 98°C), with a 9,000-litre-a-minute source; day bathing 10:00-15:00, closed in winter.
Last official check
25 Sept 2026
Traveler reports
0
Reports open in Phase 2
Next scheduled check
24 Dec 2026
Before you go
Only facts we confirmed on official sources are shown. Anything else is marked “Not checked yet”.
- Opening hours
Day bathing 10:00-15:00 (last entry 14:30).
Checked 25 Sept 2026 on the official site- Closed
Closed in winter (November 30 to mid-April); the sister inn Shin-Tamagawa Onsen stays open.
Checked 25 Sept 2026 on the official site- Admission
Day bathing: adults 1,000 yen, children 500 yen (from April 16, 2026).
Checked 25 Sept 2026 on the official site- Getting there
In the summer season (late April to late November) you can come by car, taxi or bus. Route 341 closes at night (19:00-8:00) just after it opens in spring and just before it closes in autumn.
Checked 25 Sept 2026 on the official site- Parking
Day visitors use the prefectural Tamagawa park car park on the way down to the inn (about 8:30-16:30, 300 yen per visit).
Checked 25 Sept 2026 on the official site- Payment
Not checked yet — we have not confirmed this on an official source yet. Check with the spot before you go.
- Accessibility
Not checked yet — we have not confirmed this on an official source yet. Check with the spot before you go.
Found wrong or outdated information? Let us know
Address: Semboku, Akita (Japanese address: 秋田県仙北市田沢湖玉川渋黒沢)
Official site: https://www.tamagawa-onsen.jp/
Location
Smaller pins are other spots nearby.
Nearby spots
Photo: 掬茶 / Wikimedia Commons, CC BY-SA 3.0 (resized)Goshogake OnsenAkita6 km away (straight line)
Photo: SAGI1955 / Wikimedia Commons, CC0 (resized)Hachimantai Dragon Eye, Kagami-numa PondAkita11 km away (straight line)
Photo: Thyristorchopper / Wikimedia Commons, CC BY-SA 3.0 (resized)Hachimantai Aspite LineIwate17 km away (straight line)- No photo yetTsurunoyu Onsen, Nyuto Onsen VillageAkita19 km away (straight line)
- No photo yetKuroyu Onsen, Nyuto Onsen VillageAkita20 km away (straight line)
Distances are straight-line distances, not travel distances.
Crowds
- Crowd level
Not checked yet — no official source yet, and not enough traveler reports.
- Best time to visit
Not checked yet — no official source yet, and not enough traveler reports.
- Peak time
Not checked yet — no official source yet, and not enough traveler reports.
- Busiest days
Not checked yet — no official source yet, and not enough traveler reports.
- Busiest season
Not checked yet — no official source yet, and not enough traveler reports.
- Latest traveler report
- None yet
Traveler crowd data by time of day appears after 5 traveler reports (0 so far).
Visiting respectfully
- Local etiquetteBecause of bears, avoid going out at night or early morning and don't eat on the nature trail (natural bedrock bath area); carry a bear bell and walk in groups (bells and trekking poles are lent free).Checked 25 Sept 2026 on the official site
- Local etiquetteThe main bath is built of Aomori hiba cypress with 11 kinds of baths; the 100% source-water bath is very strong.Checked 25 Sept 2026 on the official site
Verification log
- 25 Sept 2026First check · Official website · https://www.tamagawa-onsen.jp/care/Hours and fees read from the official site.
- 25 Sept 2026First check · Official website · https://www.tamagawa-onsen.jp/Fees, access and parking read from the official site.
- 25 Sept 2026First check · Official website · https://www.tamagawa-onsen.jp/access/Hours, closing days, cautions and rules and seasons read from the official site.
- 25 Sept 2026First check · Tourism board · https://akita-fun.jp/spots/89Closing days, seasons and coordinates read from a tourism organization's site.