Nagasaki · Obama Onsen (Nagasaki)
Obama Onsen Wakihama Public Bath (Otasshan-yu)
小浜温泉 脇浜共同浴場「おたっしゃん湯」
A communal bath in Obama Onsen on Tachibana Bay, whose ~100°C springs release more heat than any in Japan. The single-storey wooden building from 1937 feels like a museum of Showa-era life and is a designated prefectural townscape asset. Pay at the old-style counter, then choose between the hot and very hot tubs of free-flowing chloride water. Open from 6 am; part of the Kyushu 88 Onsen trail. About an hour from Nagasaki city, on the way back from Unzen.
- Price (adult)
- ¥200
- Hours
- 6:00–21:00 (varies by season)
- Closed
- Open daily (occasional closures)
- Access
- 5 min walk from Obama bus stop (Shimatetsu Bus); 60 min by car from Nagasaki city
- Water type
- Simple spring
- Tattoos
- Ask ahead
- Admission
- About ¥200 (confirmed 2020; sources range ¥150–300 — pay cash at the counter and check on site). Some inns say their guests bathe free, but a contribution is appreciated. No soap or shampoo (bring or buy). No lockers — basket changing. Bring a towel
- Baths
- A wooden single-storey communal bath founded in 1937 and little changed since, designated a Nagasaki 'townscape heritage asset'. A bandai counter greets you inside, with a high ceiling and a changing room like a museum of Showa-era life. One tiled pool per sex (about eight bathers), divided by a central partition into the hot side by the spout and a cooler side. Green tiles give the water a jade tint. No rotenburo or sauna. Source tank at the rear. Southern end of the spa town, near the sea
- Spring water
- Sodium chloride spring (hypotonic, mildly alkaline, high-temperature), source about 100–105°C. Obama's thirty sources yield 15,000 tonnes a day at around 100°C — Japan's greatest 'heat output' (temperature × flow) — and here the source enters by iron pipe with tap water run alongside to temper it, free-flowing with no chlorine. The dilution softens the salt, making it gentler than the inns' water; many remark how soft it feels. Faintly bluish and clear, lightly salty. Indicated for poor circulation, neuralgia, skin disease and cuts. Obama is an ancient spring recorded in the Nara-period Hizen gazetteer; in 1684 the Shimabara lord appointed a 'yudayu' bath magistrate
- Access & parking
- No dedicated parking (use the municipal or seafront lots in the spa town, about 5 min on foot). About 1 hour by Shimatetsu bus towards Kuchinotsu/Obama from JR Isahaya Station; 5 min on foot from 'Obama Taiikukan-mae' or 10 min from the 'Obama Onsen' terminal. About 30 km / 40 min from Isahaya IC on the Nagasaki Expressway via Route 57. Unzen Hells 25 min by car
- Phone
- 0957-74-3402
- Official site
- obama.or.jp ↗
- Open in Google Maps
- Google Maps ↗
Essentials
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Why go
- Showa-era bathhouse from 1937
- Japan's hottest-output springs
- Open from 6 am
A wooden bathhouse unchanged since 1937 — Japan's 'hottest' spring for small change
Obama Onsen's Wakihama communal bath, known to all as 'Otasshan-yu', is a small bathhouse at the southern end of the Obama spa town on the west coast of the Shimabara peninsula in Unzen, Nagasaki, looking out over Tachibana Bay. Obama is an ancient spring recorded in the Nara-period Hizen gazetteer; its thirty sources yield 15,000 tonnes a day at around 100°C, giving it Japan's highest 'heat output' (temperature times flow), and the seafront is famous for a 105-metre foot bath and 'steam kettles' that cook food in hot-spring vapour. Otasshan-yu has used the same wooden single-storey building since opening in 1937 and is a designated Nagasaki townscape heritage asset; hand a few coins (about ¥200) to the attendant and you step beneath a high ceiling to a tiled tub glowing jade-green as the hot spring pours in without pause. Set a little apart from the tourist strip, it is the residents' parlour and a stop on the 'Kyushu Onsen-do' pilgrimage.
Diluted yet remarkably fresh — a bandai counter and a Showa changing room
Open the door and the bandai counter is right there; pay and split left and right. The changing room is pure Showa — wooden baskets, an old scale, a fan turning under the high ceiling — and there are no lockers, so leave valuables behind. In the middle of the bathroom sits one low tiled tub, split by a partition: the side where the spring gushes from an iron pipe is hot, the other a little milder. Because the source exceeds 100°C a water pipe runs alongside to temper it, but there is no chlorine and the flow is generous, so the water is fresh; thanks to the dilution it is less salty than the inns' 'seawater' baths, and many say it wraps the body more softly. The clear water, jade-tinted by the green tiles, tastes faintly of salt and leaves you warm and unsticky. Bring your own soap and shampoo, douse yourself well before the hot side and keep dips short. It opens at 6 a.m., and mingling with residents for a morning soak after a beach walk, trading an 'otasshan' ('stay well') greeting, is the real pleasure here.
Changing prices and hours, and enjoying Obama
Hours are generally 6:00–21:00 but may shift in summer and winter (at one time it opened at 8:00); there is no fixed closing day, though it occasionally closes without notice. The price was ¥200 as of 2020 — earlier ¥150, some sources ¥300 — so confirm at the counter. With no car park, use the municipal or seafront lots and walk five minutes. Obama's classic itinerary: the 105-metre seafront foot bath 'Hot Foot 105', steaming eggs, vegetables and seafood in the steam kettles, the sunset over Tachibana Bay, and a morning dip at Otasshan-yu. Add the Unzen Hells 25 minutes away for a full Shimabara-peninsula day, and do not miss Obama champon noodles and local sashimi. Comparing it with the municipal 'Hama-no-yu' seaside bath reveals how dilution changes the water. The bus from Isahaya takes an hour, so a rental car is convenient.
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
Mood & scenery
Price
Who with
Convenience
Amenities
✔ Verified operating: 2026-09 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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Shimabara Onsen Yutorogi-no-yu
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