Yamanashi · Nirasaki & Asahi Onsen
Nirasaki Asahi Onsen
韮崎旭温泉 韮崎旭の湯
A lone day-bath building among the fields on the outskirts of Nirasaki, north-west of the Kōfu basin, and a nationally known pilgrimage spot for onsen lovers. Nothing is added or altered – no dilution, heating, recirculation or chlorine – and as you settle into the tepid 38°C sodium chloride-bicarbonate spring, your whole body is coated in fine bubbles, said to be among the most abundant in Japan. The faintly greenish-yellow water carries a whisper of sulfur and iron, and the source running from a tap in the bathroom can be drunk (fizzy, iron-tinged). There is no open-air bath or sauna – just one big indoor pool and washing stations, like a sentō – but the windows frame the Yatsugatake and Kayagatake peaks, and the mild water makes an hour disappear. Adults pay ¥750 from outside the city (¥650 for residents) and children ¥500/¥400, rates revised on 15 April 2026 and cash only; soap and shampoo provided. Open 10:00–20:00, closed Tuesdays (next day if a holiday) and Fridays, with free parking for 25 cars. About 10 minutes by taxi from Nirasaki Station on the JR Chūō Line or 15 minutes from Nirasaki IC on the Chūō Expressway.
- Price (adult)
- ¥750
- Hours
- 10:00-20:00
- Closed
- Tuesdays (next day if holiday) & Fridays
- Access
- About 10 min by taxi from Nirasaki Station (JR Chūō Line); about 15 min by car from Nirasaki IC on the Chūō Expressway; city bus from Nirasaki Station to 'Nangū Jinja', then 5 min on foot
- Water type
- Bicarbonate spring
- Tattoos
- Ask ahead
- Admission
- Bathing adults ¥750 from outside the city / ¥650 for residents, elementary and younger ¥500 / ¥400, residents aged 75 and over ¥550 (rates revised 15 April 2026). Cash only, via a ticket machine. Shampoo and body soap provided, free lockers with keys, one hair dryer, towels sold. No rotenburo and no sauna. Free parking for 25
- Baths
- A day-use onsen of nationwide renown standing alone among fields and orchards on the north-west edge of the Kōfu basin, in the outskirts of Nirasaki. There is no rotenburo and no sauna, only one large indoor tub and five washing places — a sentō-like simplicity — but that one tub is special: soak in water that is 100% free-flowing source water with no added water, heating, circulation or disinfection, and fine bubbles cling densely over the whole body. The rest room is a 21-mat tatami room with a wooden deck terrace, from which Mt. Yatsugatake and Mt. Kayagatake can be seen
- Spring water
- A sodium chloride and hydrogen carbonate spring welling from bedrock 1,200 m down. The source is around 40°C, a lukewarm water, and the tub itself runs at 36–38°C, so you can stay in a long time. Weakly alkaline and faintly emerald-green (jade or yellow-green depending on conditions), with a slight scent of iron and sulphur, its clinging carbonated bubbles are called 'the largest in Japan'. The source water from the tap in the bathhouse can also be drunk, and is said to settle the stomach and bowels
- Access & parking
- About 10–12 minutes by taxi from Nirasaki Station on the JR Chūō Line, or about 12 minutes by bus to 'Nirasaki Ōmura Museum', then 2 minutes on foot. By car about 15 minutes from Nirasaki IC on the Chūō Expressway, 30 from Kōfu city, about 2 hours from Tokyo. Free parking for 25 (it fills early at weekends). There is no convenience store nearby, so bring cash and a towel
- Phone
- 0551-23-6311
- Official site
- nirasaki-kankou.jp ↗
- Open in Google Maps
- Google Maps ↗
Essentials
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Why go
- Pure free-flowing spring – nothing added, nothing altered
- Famous fizzy 38°C soak; drinkable source water
- ¥750 adults; closed Tue & Fri; one tub facing Mt. Yatsugatake
A single tub of 100% source water whose bubbles cover the body
Nirasaki Asahi Onsen is a small day-use onsen in Nirasaki, Yamanashi, standing alone among fields and orchards on the north-western edge of the Kōfu basin. The building is not large and the sign is plain, so first-time visitors easily drive past, yet among onsen devotees it is called the finest water in Yamanashi and people come from all over the country. The reason is one thing: the water. The source wells from bedrock 1,200 m down, and this facility applies no added water, heating, circulation or disinfection at all — it is 100% free-flowing source water, and the tub overflows at every edge, so the water is always fresh. It is a sodium chloride and hydrogen carbonate spring at around 40°C at the source, a lukewarm water, and the tub runs at 36–38°C, so it is not hot and you can stay in a long time. And what astonishes most in that lukewarm water is the bubbles. Fine carbonated bubbles cling densely over the body and form a silver-gleaming layer; this 'largest in Japan' bubble effect covers the whole body within minutes of entering, scattering when you move and reattaching. The colour shifts from faint emerald-green to jade, yellow-green or pale brown depending on conditions, and there is a slight scent of iron and sulphur. There is no rotenburo and no sauna in the bathhouse — only one large indoor tub (one for each sex), five washing places and a changing room, a sentō exactly as it is. But that simplicity is the character of this onsen: everything but the water has been stripped away and only the water remains. The source water from the tap in the bathhouse can also be drunk (it tastes of carbonate and iron) and is said to settle the stomach and bowels. Shampoo and body soap are provided at the washing places, the lockers in the changing room are free, and there is only one hair dryer, so there may be a wait at weekends. The rest room is a 21-mat tatami room with a wooden deck terrace, and from the terrace the ranges of Mt. Yatsugatake and Mt. Kayagatake spread out. Rates were revised on 15 April 2026 to ¥750 for adults from outside the city (¥650 for residents) and ¥500 for elementary and younger (¥400 for residents), paid in cash at a ticket machine. Hours are 10 a.m. to 8 p.m., closed Tuesdays (the next day if a holiday) and Fridays, and with parking for 25 that fills early at weekends it is worth going early.
A long soak in lukewarm water, and how to enjoy this onsen
Park (25 free spaces), go in and buy a ticket in cash at the machine (¥750 for adults from outside the city). The shoe lockers have no keys, the changing-room lockers are free, and towels are sold if you have none. A recommended order: wash at the washing places; get into the tub and stay still — after five to ten minutes without moving, bubbles cover the body; then a long soak of 20–40 minutes with the bubbles on you — at 36–38°C you can stay long without tiring, and this is the heart of the onsen; move to scatter the bubbles and let them reattach; get out and take a light shower (using much soap washes away what remains on the skin); drink a mouthful of the source water from the tap (it can be drunk); and rest in the 21-mat rest room until the sweat subsides. The sodium chloride and hydrogen carbonate water is slick, and the carbonated bubbles aid circulation, so warmth stays long after you get out. With no rotenburo and no sauna it does not suit anyone whose aim is 'a sauna too'; it is for those who want to enjoy the water itself at length. Notes: cash only (no cards or QR); closed Tuesdays and Fridays; open until 8 p.m.; one hair dryer; crowded weekend afternoons and a full car park; no rotenburo; and with children the lukewarm water is in fact safer. Nirasaki Asahi Onsen competes on water rather than facilities, and is worth one stop on a journey around Kōfu or Yatsugatake.
Practical details and a Yamanashi onsen round
Hours are 10:00–20:00, closed Tuesdays (the next day if a holiday) and Fridays; adults ¥750 from outside the city / ¥650 for residents, elementary and younger ¥500/¥400 (revised April 2026); cash only; free parking for 25. Access is 10–12 minutes by taxi from Nirasaki Station, 15 from Nirasaki IC, 30 from Kōfu city. Suggested routes: (1) a bath round of Nirasaki — Asahi Onsen (carbonated) plus the town's two other day-use onsen (¥700 and ¥900 for adults), to compare different waters in one day; (2) Yatsugatake — Kiyosato and Kobuchizawa, Asahi Onsen, home via the Chūō Expressway; (3) a day in Kōfu — the Takeda Shrine and Shōsenkyō gorge, Asahi Onsen, Kōfu Station; (4) a long-soak expedition — enter around 3 p.m., soak two hours, rest in the rest room; (5) a view of Mt. Fuji — look out at Fuji and Yatsugatake from the terrace before bathing. Notes: cash only; closed Tuesdays and Fridays; open until 8 p.m.; the car park fills at weekends; no rotenburo or sauna; no convenience store (bring a towel and a drink). Many say that if you visit only one carbonated spring in Japan it should be this one, and it deserves to be the centre of a trip in Yamanashi.
Before you go
- No official tattoo policy is published — ask at reception.
- Payment is usually by ticket machine in cash — bring coins.
- Last entry is 30–60 minutes before closing.
Features
Mood & scenery
Price
Who with
Convenience
Amenities
✔ Verified operating: 2026-10 Operating status and rates cross-checked against the official site and onsen guides (full source notes in Japanese on the JA page)
Prices and hours change. Check official sources before visiting.
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