A ryokan surrounded by breathtaking, dreamlike open-air hot spring views and the soothing sounds of the shamisen.
Olkawaso, located in Ashinomaki Onsen in Aizuwakamatsu City, Fukushima Prefecture, is a hot spring ryokan renowned for its lobby, which is said to resemble the Infinity Castle from the popular anime Demon Slayer: Kimetsu no Yaiba.
With a dreamlike atmosphere filled with the live sounds of the shamisen and open-air baths offering breathtaking views of the gorge, guests can experience the very essence of traditional Japanese culture.
Founded in 1953, this long-established ryokan stands gracefully along the mountain stream of Ashinomaki Onsen. Its soaring, open-atrium lobby features a striking floating stage where the resonant sounds of the shamisen fill the space, showcasing the breathtaking beauty of traditional Japanese architecture.
From the open-air baths terraced like rice fields and facing the gorge, guests can enjoy spectacular seasonal views throughout the year, spending an extraordinary moment surrounded by Japanese tradition and pristine nature.
Natural hot spring with continuously flowing water
Pickup and drop-off service available
Okami (female innkeeper)
Private bath available (exclusive-use bath)
In-room bath available
IN 15:00 (Last check-in: 6:00 PM) / OUT 10:00
About Ookawaso
Ookawaso is a long-established ryokan located in Aizuwakamatsu City, Fukushima Prefecture. It first opened in 1953 as the very first ryokan in the Ashinomaki Onsen area. Surrounded by stunning views along a mountain stream, the ryokan offers a chance to fully enjoy both rich natural scenery and traditional Japanese hospitality.
The moment you step into the lobby of Ookawaso, you are greeted by a breathtaking sight. The space features a dramatic open-air design that extends from the basement level up to the first floor. At the center is a floating stage, surrounded by a circular corridor, creating a truly unique architectural structure. This atmospheric lobby has gained attention on social media for its resemblance to the Infinity Castle from the popular manga and anime Demon Slayer. As a result, Ookawaso has become especially popular among younger travelers.
All guest rooms face the Okawa Gorge, allowing guests to relax while enjoying magnificent valley views that change with the seasons. With its powerful natural surroundings, one-of-a-kind architecture, and deep connection to Aizu’s traditional culture, Ookawaso can truly be described as a special and unforgettable ryokan.
Floating Stage
A floating stage that became a hot topic on social media for its resemblance to the Infinity Castle from the popular manga Demon Slayer
Dinner&Breakfast
Dinner is a regional kaiseki course featuring an abundance of seasonal Aizu ingredients. Each dish is carefully prepared to highlight the natural flavors of fresh local produce sourced that day—delicacies you can experience only here in Aizu. The menu includes Aizu specialties such as horse-meat sukiyaki, fresh seasonal sashimi, and Aizu soba. For the main course, guests can choose between a beef steak or a fish dish. A wide selection of local Aizu sake is also available, and guests can enjoy rare labels from local breweries, including Hiroki and Sharaku, which are especially popular when paired with the meal.
Dinner is served in one of several dining spaces, depending on the day. Guests may dine at the refined dining area “Bimikyushin KAWADOKO,” the large banquet hall (Japanese-style dining hall), or the small banquet hall. At Bimikyushin KAWADOKO, meals are enjoyed in private or semi-private spaces separated by sliding doors. With the gentle sound of the river as background music, guests can relax and savor their kaiseki meal at a leisurely pace.
Breakfast is offered as a Japanese, Western, and Chinese buffet, served in an open and airy dining space overlooking the gorge. While enjoying views of the flowing river, guests can take their time selecting from a wide range of dishes made with fresh local ingredients. One of the most popular items is the live kitchen specialty, “fluffy egg over rice.”This dish features light, whipped egg whites topped with a rich egg yolk from locally raised Aizu chicken, finished with lightly grilled seaweed. With such a generous variety to choose from, guests will likely fin
Dinner
Local Aizu Kaiseki Cuisine
A beautifully presented kaiseki meal crafted with an abundance of seasonal ingredients nurtured by Aizu’s rich natural environment. While honoring traditional regional recipes, each dish is finished with a modern touch by skilled chefs.
Onsen(Hot Spring)
One of the highlights of Ookawaso is its scenic open-air baths set along the mountain stream, along with a variety of bathing areas. Among them, the most famous is the open-air bath known as “Shikibutai Tanada,” celebrated for its spectacular views. The baths are arranged in a terraced style, and from each level you can enjoy a wide panoramic view of the Okawa Gorge right in front of you. As you soak in the hot spring, the gentle sound of the flowing river softly reaches your ears. The roof, made of hinoki cypress wood, releases a pleasant natural aroma. Surrounded by these sights, sounds, and scents, you can enjoy a truly luxurious bathing experience while feeling deeply connected to the nature of Ashinomaki. The baths are arranged in three tiers for both the men’s and women’s areas. Each bath is a generous free-flowing hot spring, carefully temperature-controlled by dedicated bath attendants. Special design features ensure that water overflowing from the upper baths does not flow into the lower ones, keeping every bath constantly filled with fresh, pristine hot spring water.
Another signature bath at Ookawaso is the Sky Open-Air Bath. Inspired by the stage of Kiyomizu-dera in Kyoto, this elevated bath extends out over the gorge, offering a thrilling view straight down to the flowing Okawa River below. Reached by climbing 123 steps, the bath allows you to immerse yourself in dramatic seasonal scenery—cherry blossoms in spring, fresh greenery in summer, vivid autumn leaves, and snow-covered landscapes in winter. In the early morning, the bath is open separately for men and women. From 1:00 PM to 10:00 PM, it becomes a private bath, creating a romantic experience where you can enjoy the illuminated gorge at night all to yourself.
The hot spring water is a calcium–sodium sulfate–chloride type, with a high temperature of over 60°C and an abundant flow. It is said to be effective for relieving nerve pain and fatigue. The large indoor bath also features wide windows overlooking the gorge, allowing you to relax and stretch out while enjoying the changing seasons. In addition, unique sauna facilities are available, including a pink salt sauna (for men) and a stone bed sauna made with barley stones (for women). Both are low-temperature saunas, gentle on the body and ideal for slow, deep relaxation.
Onsen
Terraced-Style Open-Air Baths
“Shiki-butai Tanada,” the signature open-air bath of Ookawaso, is designed in the shape of traditional terraced rice fields. As you soak, you can hear the gentle flow of the river and enjoy a deep sense of unity with the surrounding nature.
Rooms
Guest rooms are available in more than seven different styles, ranging from traditional Japanese rooms to Western-style rooms. All rooms offer an excellent location, with wide windows opening out to beautiful views of the gorge. Surrounded by greenery and the gentle sound of the stream, guests can relax while enjoying the powerful natural scenery that changes with the seasons.
The ryokan has two distinct accommodation wings. Yomachi-tei features a calm Japanese-modern design, blending traditional Japanese aesthetics with modern comfort. Tsukimi-tei, on the other hand, offers a more traditional Japanese style at a more affordable price, including classic tatami rooms and larger special rooms with connected spaces. With a wide variety of room types available, guests can choose the perfect option to suit their budget, group size, and travel style at Ookawaso.
The corner VIP suite on the top floor is especially popular. Featuring spacious tatami rooms measuring 12.5 and 6 mats along with an additional Western-style room, this suite offers an open and luxurious layout. Surrounded by tasteful furnishings, guests can enjoy an elegant and relaxing stay. The ryokan also offers barrier-free twin rooms, making it a comfortable choice for elderly guests or those using wheelchairs. All rooms are equipped with Wi-Fi, unit baths, washlet toilets, refrigerators, and yukata robes, ensuring a comfortable stay. Upon arrival, guests are treated to traditional Japanese sweets, such as Aizu-style yōkan made with salt from the hot spring water. At night, the sky outside the windows fills with stars, and the gentle sound of the river creates a peaceful backdrop for restful sleep.
Particularly noteworthy are the newly renovated VIP Rooms, which reopened in 2025. Located in the Tsukimi-tei wing, the VIP Room and VIP Twin feature a private open-air bath and sauna, allowing guests to enjoy hot springs and relaxing sauna time whenever they wish, all within the comfort of their own room. Set in corner rooms overlooking the Okawa River, these accommodations offer a highly private and indulgent experience. The VIP Twin accommodates up to two guests, while the VIP Room can host up to four, making them popular not only with couples and married pairs but also with friends traveling together. After enjoying the private sauna, guests can unwind in the fragrant cypress-scented hot spring bath—a truly luxurious experience available only in these VIP rooms.onke Ogiya with a visit to Yunokami Onsen makes for a well-balanced and relaxing travel plan.
Room
Comfort Twin Room
Blending the comfort of traditional tatami flooring with modern living, this room features Simmons beds for a restful night’s sleep. After enjoying views of the Okawa River’s natural beauty from the window, relax and unwind in a functional, high-quality bed that gently eases travel fatigue.
Special Experience
When visiting Ookawaso, one experience not to be missed is the live shamisen performance on the floating stage. Located at the center of the lobby’s dramatic open atrium, the floating stage hosts live shamisen music timed to coincide with check-in. The rich, emotional sound of the instrument echoes throughout the space, blending beautifully with the gentle murmur of the Okawa River flowing just outside and setting an elegant tone for the journey ahead.
The architecture of the lobby has often been compared to the Infinity Castle from the manga and anime Demon Slayer: Kimetsu no Yaiba, but the resemblance goes even further. Watching a female performer in a traditional kimono play the shamisen on the floating stage closely recalls the character Nakime, who plays the biwa in the series. The scene feels so much like a moment from the anime that it has become a popular topic on social media, praised for its dreamlike and cinematic atmosphere.
Guests can also enjoy the performance while relaxing in the adjacent lounge with a drink in hand, listening to the music at their own pace. This graceful blend of live music, architecture, and natural surroundings offers a memorable and refined start to a stay at Ookawaso.
Floating Stage
A Breathtaking Atrium
The sight of the floating stage set beneath a dramatic open atrium rising from the basement is truly breathtaking. The vivid red carpet stands out beautifully in the expansive space, and in recent years, the scene has gone viral on social media for resembling the Infinity Castle from the popular manga and anime Demon Slayer: Kimetsu no Yaiba.
Plan List
This service operates on a reservation request basis. We first check room availability with the accommodation and then suggest the most suitable room and plan for you. After availability is confirmed, we will send our proposal via LINE. Your reservation will be confirmed once payment is completed.
Plans
Standard Plan – 1 Night, 2 Meals Included (Okawaso)
Check-in 15:00~18:00 / Check-out 10:00
Online-Card Payment
Local Payment
Meal Included
Total27,800~/per JPY ~
1 Night with Breakfast Plan – No Dinner (Okawaso)
Check-in 15:00~18:00 / Check-out 10:00
Online-Card Payment
Local Payment
Meal Included
Total18,500~/per JPY ~
Premium Dining Plan | 1 Night with Dinner & Breakfast | Okawaso
Check-in 15:00~18:00 / Check-out 10:00
Online-Card Payment
Local Payment
Meal Included
Total30,400~/per JPY ~
Access
Address 984 Shimodaira, Ashinomaki, Otomachi, Aizuwakamatsu City, Fukushima 969-5147, Japan
By Train
From Asakusa (Tokyo area)
Tobu Railway Limited Express “Liberty” → Aizu-Tajima Station (direct)
Transfer to Aizu Railway → Ashinomaki-Onsen Station
Approx. 4 hours
From Niigata area
JR Ban’etsu West Line (Rapid) → Aizuwakamatsu Station
Transfer to Aizu Railway → Ashinomaki-Onsen Station
Approx. 2 hours 45 minutes
By Bullet Train
Tokyo → Koriyama: approx. 1 hour 30 minutes (Tohoku Shinkansen)
Train to Ashinomaki-Onsen Station: approx. 1 hour 30 minutes
Highway bus to Ashinomaki Marumine-mae Bus Stop: approx. 1 hour 45 minutes
Bullet Train & Rental Car
Via Shin-Shirakawa (from Tokyo area)
Approx. 1 hour 15 minutes via National Route 289
※ During the snowy season, it is recommended to avoid mountain roads and use the Koriyama JCT route below.
By Car
Via Tohoku Expressway
From Tokyo area
Approx. 3 hours 30 minutes
Tokyo → Koriyama JCT (approx. 2 hours 30 min)
Koriyama JCT → Aizuwakamatsu IC (approx. 30 min)
Aizuwakamatsu IC → Ookawaso (approx. 35 min)
From Sendai area
Approx. 2 hours 25 minutes
Sendai-Minami IC → Koriyama JCT (approx. 1 hour 20 min)
Koriyama JCT → Aizuwakamatsu IC (approx. 30 min)
Aizuwakamatsu IC → Ookawaso (approx. 35 min)
Via Ban’etsu Expressway
From Niigata area
Approx. 1 hour 50 minutes
Niigata → Aizuwakamatsu IC (approx. 1 hour 15 min)
Aizuwakamatsu IC → Ookawaso (approx. 35 min)
Free Shuttle Service
A complimentary shuttle bus is available from Ashinomaki-Onsen Station. Travel time is approximately 5 minutes by car.
Basic Information
Ryokan Name
Ookawaso
Address
984 Shimodaira, Ashinomaki, Oto-machi,
Aizuwakamatsu City, Fukushima 969-5147, Japan
Baths
Spring Quality
**Sodium–Calcium Sulfate–Chloride Hot Spring**
Free-flowing
源泉掛け流し
Facilities & Features
○Hot spring
○Free-flowing natural hot spring water
○Large public bath
○Private bath
○Open-air bath
○Guest rooms with open-air baths
○Sauna
×Stone spa (ganbanyoku)
×Within walking distance of the nearest station
○Within walking distance of a bus stop
○Convenience store within a 10-minute walk
○Free parking available
○Free shuttle service
○Barrier-free access
○Western-style rooms available
○Rooms with private toilets
○Rooms with a private bathroom and toilet available.
○Shamisen performance
○Esthetic salon
○Tea lounge
Common Amenities
○Hair Dryer
○Shampoo/Conditioner
○Body Soap
○Toothbrush/Toothpaste
○Body Towel
○Room Wear (Yukata)
○Indoor slippers provided
○Hairbrush
×Face wash
×Facial toner
×Lotion
×Razor
×Shaving cream
×Cotton
○TV
○Refrigerator
○Tea Set
○Electric kettle
×Washing machine
×Dryer
Frequently Asked Questions
Please tell me about private baths / family baths.+
The open-air bath in the sky is available for private use in the afternoon.
・Limited to 16 groups per day
・Fee: ¥3,300 (tax included) for 45 minutes
・Available start times: 13:00, 14:00, 15:00, 16:00, 17:00, 18:00, 20:00, 21:00
Can you store our luggage before check-in and after check-out?+
We offer free luggage storage both before check-in and after check-out.
Is there a designated smoking area?+
There is a designated smoking area next to the shop on the first floor.
Could you please tell me about dinner?+
For dinner-included plans, we serve a traditional kaiseki meal prepared with care using locally sourced ingredients from Aizu. The menu changes depending on the season.
For plans without dinner, please note that there are no restaurants within the property available for casual dining.
If you have booked a **one-night stay with breakfast only (no dinner) plan, we are unable to arrange dinner upon same-day request. Thank you for your understanding.
