Yamagata, Yamagata / 蔵王温泉大露天風呂
Zao Onsen Dai-rotenburo Open-air Bath
Large rock pools beside a mountain stream at Zao Onsen, fed by one of Japan's most acidic sulphur springs (pH 1.9); open from late April until 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
Weekdays 9:30-17:00 (last entry 16:30); weekends and holidays 9:30-18:00 (last entry 17:30). The 2026 season opened on April 25.
Checked 25 Sept 2026 on the official site- Closed
Closed in winter (about late November to late April; may change with snow). In 2026 it also closed for maintenance on June 4 and July 13.
Checked 25 Sept 2026 on the official site- Admission
Adults 850 yen, children (1 to under 12) 400 yen.
Checked 25 Sept 2026 on the official site- Getting there
About 20 km (35 min) from Yamagata-Zao IC via Route 13 and Prefectural Road 21. Yamako bus from JR Yamagata Station to the Zao Onsen terminus, then 18 min on foot. The road is very narrow, so drive carefully. For car navigation enter 023-694-9718 (it shows "Terrace Sanpal" but leads to the bath's car park).
Checked 25 Sept 2026 on the official site- Parking
Car park for bath users (60 spaces).
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
The baths are reached by going down stairs after the gate.
Checked 25 Sept 2026 on the official site
Found wrong or outdated information? Let us know
Address: Yamagata, Yamagata (Japanese address: 山形県山形市蔵王温泉荒敷853-3)
Official site: http://www.jupeer-zao.com/roten/
Location
Smaller pins are other spots nearby.
Nearby spots
Photo: Yamagata Prefecture (yamagatakanko.com)Zao Ropeway (snow monsters)YamagataLess than 1 km away (straight line)
Photo: Σ64 / Wikimedia Commons, CC BY 4.0 (resized)Zao Okama Crater LakeMiyagi5 km away (straight line)- No photo yetBunshokan (former Yamagata Prefectural Office)Yamagata11 km away (straight line)
- No photo yetYamagata Castle Ruins, Kajo ParkYamagata12 km away (straight line)
- No photo yetKami-no-yu public bath, Togatta OnsenMiyagi16 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
Starry-night bathing by lantern light on set nights from June to early October 2026, 18:30-21:00 (last entry 20:30), adults 1,000 yen, children 500 yen; October dates are the 3rd, 10th and 11th.
Checked 25 Sept 2026 on the official site- 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 the spring water flows straight through, there are no showers and soap and shampoo cannot be used. Towels are sold and coin lockers are available.Checked 25 Sept 2026 on the official site
- RulesStrongly acidic water: rinse before entering, do not scrub hard, keep it out of your eyes, do not drink it, remove jewellery (metals turn black), keep it off clothing, and watch for slippery floors.Checked 25 Sept 2026 on the official site
Verification log
- 25 Sept 2026First check · Official website · http://www.jupeer-zao.com/roten/Hours, closing days, access, parking and cautions and rules read from the official site.
- 25 Sept 2026First check · Tourism board · https://yamagatakanko.com/attractions/detail_2764.htmlClosing days, seasons and coordinates read from a tourism organization's site.