Iwate · Hanamaki Onsen
Osawa Onsen Jisuibu Tojiya
大沢温泉 自炊部「湯治屋」
A wooden toji (therapeutic stay) inn over 200 years old on the Toyosawa River in the Hanamaki-Minami onsen area, once frequented by poet Kenji Miyazawa. Its signature is 'Osawa-no-yu', a mixed open-air bath jutting over the river, with women-only hours. Day bathing from 7 am; ¥700 covers three baths. Many linger for lunch and sake at the 'Yahagi' dining room. Free shuttle from Hanamaki Station.
- Price (adult)
- ¥700
- Hours
- 07:30–21:00 (last entry 20:30)
- Closed
- Open daily
- Access
- 30 min by free shuttle from JR Hanamaki Station, or local bus to Osawa Onsen
- Water type
- Alkaline simple
- Tattoos
- Ask ahead
- Admission
- Adults ¥700 / children ¥400 (pay at the self-catering wing desk). Bath towel rental ¥100. Soap and shampoo in the indoor bath (not at the rotenburo). Self-catering stays (a few thousand yen a night) also possible; many long-stay guests
- Baths
- An old therapeutic spa in wooden buildings over 200 years old. The mixed riverside rotenburo “Osawa-no-yu” on the Toyosawa River (women-only hours), the women-only rotenburo “Kawabe-no-yu”, the gender-separated indoor “Yakushi-no-yu”, and the semi-open “Toyosawa-no-yu” in the adjoining Sansuikaku wing (also open to day visitors)
- Water
- Alkaline simple spring, source about 51 °C, clear with a soft silky feel. All tubs free-flowing. Famous as the onsen Miyazawa Kenji often visited with his father as a boy
- Parking
- 120 free spaces. Free shuttle from Hanamaki and Shin-Hanamaki stations (Hanamaki-minami spa loop, reservation) or Iwate Kenkotsu bus ~30 min to “Osawa Onsen”. 15 min from Hanamaki-minami IC (Tohoku Expressway)
- Phone
- 0198-25-2021
- Official site
- oosawaonsen.com ↗
- Open in Google Maps
- Google Maps ↗
Essentials
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Why go
- 200-year-old toji inn
- Mixed rotenburo over the river
- Day use from 7 am
The riverside mixed bath Kenji loved — time slows in a 200-year-old therapeutic inn
Osawa Onsen is an old therapeutic spa in the Toyosawa River valley south of Hanamaki, Iwate — the “Hanamaki-minami spa gorge” — where the modern Sansuikaku inn, the tatami Kikusuikan and the “Jisuibu Tojiya” self-catering wing, still using wooden buildings over 200 years old, stand eave to eave. Day visitors pay ¥700 at the self-catering wing, where creaking corridors, the communal kitchen and the daily life of long-stay guests survive intact, as if you had stepped back into the Showa era. Its emblem is the mixed riverside rotenburo Osawa-no-yu, almost unscreened, facing the Toyosawa River and the hills opposite, where alkaline simple spring water from a roughly 51 °C source overflows unheated. Women have reserved hours and a separate women-only rotenburo, Kawabe-no-yu, and there are also the gender-separated indoor Yakushi-no-yu and the semi-open Toyosawa-no-yu in the adjoining Sansuikaku — four baths to tour in all. It is also known as the onsen where Miyazawa Kenji often stayed as a boy with his father for Buddhist study retreats, pairing well with a “Kenji’s hometown” itinerary. A free reservation-only shuttle runs from Hanamaki Station, and a self-catering night costs just a few thousand yen — if you have time, stay over and sit alone in the steaming Osawa-no-yu at dawn.
Tips & cautions
- Day bathing 7:30–21:00 (last entry 20:30), open daily. Pay at the self-catering wing front desk.
- Osawa-no-yu is mixed and almost unscreened — women can use the reserved hours (check the notice) or Kawabe-no-yu. Follow on-site guidance on wearing a towel.
- No soap or shampoo at the rotenburo — wash in Yakushi-no-yu first.
- In winter you cross snow to reach the outdoor bath — mind your slippers.
- Toyosawa-no-yu in Sansuikaku is included in the day fee — don’t miss it.
- The free shuttle requires reservation — phone ahead.
- Tattoo policy unconfirmed — therapeutic spas tend to be lenient, but ask first.
- Self-catering stays charge separately for futon and utensils; there is also a dining hall.
Getting there
Iwate Kenkotsu bus (toward Hanamaki-minami spa gorge) ~30 min from JR Hanamaki Station (Tohoku main line) or Shin-Hanamaki (Tohoku Shinkansen) to “Osawa Onsen”, right there; or the reservation-only free shuttle (Osawa 181, Yuguchi, Hanamaki). By car ~15 min on Pref. Road 12 from Hanamaki-minami IC (Tohoku Expressway); 120 free spaces. Tel. 0198-25-2021 (self-catering wing).
Before you go
- No official tattoo policy is published — ask at reception.
- There is a mixed-gender area. Check the description for bathing garments and women-only hours.
- Ryokan day-use hours are limited and may be suspended in peak season — phone the same morning.
- Payment is usually by ticket machine in cash — bring coins.
- Last entry is 30–60 minutes before closing.
Features
Rules & private
Price
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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Oshuku Onsen Hotel Uguisu
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