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December 26, 2023
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Property Details: Hoshino Resorts KAI Poroto

Hoshino Resorts KAI Poroto is the 19th property operated by Hoshino Resorts under the hot spring ryokan brand, KAI, and has opened on 14 January 2022 in Shiraoi, Hokkaido. This is the first KAI property in Hokkaido and its concept is “a hot spring ryokan with a cone-shaped bathhouse surrounded by Lake Poroto.” It is characterized by the design in which the lake is boldly drawn into the premise, and all guest rooms face the still lake, which changes its appearance with each season. 

About KAI Poroto
Shiraoi Onsen is where moor spring, containing organic minerals derived from plants and is rare in the world, can be found. KAI Poroto is located on the edge of Lake Poroto, surrounded by the natural forests of Hokkaido, home to many wild birds. With respect to Ainu culture and the Ainu people, indigenous to Hokkaido, the architecture, art, and décor of the property were created by architect, Hiroshi Nakamura. By boldly drawing the lake into the premises as part of the facility, guests will be able to feel close to the lake. "Poroto ko" means "big lake" in the language of Ainu. The building was inspired by “Poroto-kotan” (*1), which has been maintained as a place for passing down Ainu culture. The bathhouse is unique to this property, which incorporates “ketunni” (*2), a tripod structure using logs, as its basic structure and is located near the lake. Moreover, KAI Poroto has a partnership agreement with Shiraoi town. 
*1 Village of the Ainu people 
*2 Traditional houses for the Ainu people, where the tripod structure is vital for supporting the roof.

Characteristics of KAI Poroto

  • KAI Signature Rooms – “Shikaku-no-ma”

KAI Signature Rooms are called “Shikaku-no-ma” and in Japanese, it is written □間. All of the guest rooms face Lake Poroto and were inspired by “cise,” a typical type of house of the Ainu people. All four room types have tables inspired by a square fireplace at the center of traditional cise. This was included in the rooms with the hopes that guests can surround the table, made to resemble a fireplace, for an enjoyable time. The interior is decorated with wooden oars inspired by the life of the Ainu people, and the walls and cushions are decorated with Ainu patterns. From the rooms, guests can see the calm Lake Poroto and the natural forest with white birch and maple trees. The interior design that is inspired by Ainu culture and the presence of white birch logs in the room will make one feel at one with the local culture and surrounding nature. 

  • Hot springs – Soak in the moor spring, rare among the worlds 

Moor spring
The hot spring of KAI Poroto is moor spring, which is rare in the world. Moor springs contain organic minerals derived from plants and are characteristic of their dark brown color. Humic acid with properties to promote skin regeneration and fulvic acid with skin conditioning properties are both used in cosmetics and can be found in the moor spring, otherwise known as the “springs of beauty.” In addition, since the spring quality of KAI Poroto is alkaline, the metabolism of the skin is enhanced by the removal of dead skin cells and as a result, smooth skin can be attained after bathing.
Spring quality of KAI Poroto: Alkaline, pH 8.82

At KAI Poroto, there are two hot spring facilities called “Sankaku-no-yu” and “Maru-no-yu” and in Japanese, it is represented as △湯 and 〇湯, respectively. Sankaku-no-yu is located inside the cone-shaped bathhouse and has an indoor bath and an outdoor bath. The architectural characteristic of Ainu culture, “ketunni,” a tripod structure using logs, is the basic structure of the bathhouse. There are two indoor baths, the “Atsuyu” (hot water), which flows directly from the source, and the “Nuruyu” (warm water), which calms the mind and body with its gentle warmth. In the outdoor bath overlooking Lake Poroto, guests can enjoy the scenery that changes from season to seasons, such as fresh green, autumn leaves, and snow in the open air. 

Compared to the open-air Sankaku-no-yu, the “Maru-no-yu” is a space that makes one feel as if they are in a cave or underground. It is designed so that guests can imagine the moor spring flooding out from the earth. At the top of the dome ceiling of the indoor bath, there is a round hole that connects to the environment outside, where soft light enters to illuminate the bathhouse. Together with Sankaku-no-yu, the hot spring will blend in with the surrounding environment of Poroto Lake and will aim to become a famous hot spring loved by locals.

  • KAI Local Flavors – Kaiseki course meal using local ingredients

Kaiseki course meals are served at semi-private dining rooms of KAI Poroto and use Hokkaido's specialty ingredients. The course starts with pressed potatoes with salmon roe and sea urchin on top. This is followed by a selection of appetizers of Japanese pickles and sashimi, presented on a wooden boat-shaped plate inspired by the wooden boats used during trade by the Ainu people. The main dish for the special Kaiseki course meal is a hot pot using crab and scallops. The rich bouillabaisse soup is made by stewing seafood with the addition of crab and scallops which are specialty ingredients of Hokkaido. Enjoy a private time at the dining area for a satisfying and warm dinner of local ingredients.   

  • KAI Cultural Discovery: Sachet Amulet Workshop 

One way of hospitality by the KAI properties is the KAI Cultural Discovery program. Ikema plant was warned by Ainu people on a daily basis to ward off the bad so at KAI Poroto, guests can experience sachet amulet making using this plant. Ikema is a plant with a distinct earthy scent. Ainu people have lived in harmony with nature, where it is thought that all things in nature have souls and the Ikema is said to keep bad things away. This workshop invites guests to experience the views of the nature of the Ainu people by crafting their own sachet amulets using a blend of Ikema and other herbs and wrapping it in a bag with Ainu patterns. 

Comment by architect Hiroshi Nakamura, NAP Architectural Consulting 
When I stood on the edge of Lake Poroto, I saw Mt. Tarumae in the distance, and right in front of me was a beautiful lake with no man-made objects and a natural forest. Shiraoi used to be a place where the Ainu kotan (village) used to be, and today, there is a cise (housing) village, recreated by Upopoy, on the opposite side of the premise. I decided to draw in the lake as part of the premise so that the view of the lake and the mountains can be seen from every room whilst being surrounded by the village and white birch forest. I was especially careful with the two bathhouses. One incorporates the ketunni structure, which is characteristic of Ainu architecture. And the other focused on the feeling of being held by the earth. I hope that people will appreciate the hot springs that are a blessing of nature and enjoy the experiences that can only be experienced here and the feeling of being one with nature.

Related Information
About the partnership agreement with Shiraoi town
A partnership agreement between Hoshino Resorts and Shiraoi, Hokkaido was completed on 28 June 2018. In cooperation with Shiraoi town and organizations related to Upopoy, an adjacent space that symbolizes the coexistence of ethnic groups, we will respect the Ainu culture and work together to provide an opportunity for guests to experience the Ainu culture.  

About Upopoy National Ainu Museum and Park
Opened as a National Center on 12 July 2020, as a base for the restoration and development of Ainu culture. Operated by The Foundation for Ainu Culture, its main facilities include the National Ainu Museum, which is where visitors can learn and think about Ainu culture through firsthand experiences and the National Ainu Park. Shiraoi Town has been maintained as a place of passing down Ainu culture, and as a facility rooted in the same place, we will work to cooperate with each other in the long term.

About KAI Poroto
Name: Hoshino Resorts KAI Poroto
Location: 1-1018-94 Wakakusa-cho, Shiraoi, Hokkaido 
Number of Rooms: 42
Facilities: Lobby, dining, travel library, shop, “Yuagari lounge,” Public bath – “Sankaku-no-yu” and “Maru-no-yu”
Price: Starting from 31,000 JPY per night per person in a 2 person room (includes tax and service charge, breakfast and dinner)
Direction: 15 minutes by walk from JR Shiraoi Station, 40 minutes by car from New Chitose Airport

About KAI Brand
"Japanese Auberge" in classic hot spring regions
KAI is a leading brand of hot spring ryokan where every establishment offers a contemporary take on traditional Japanese inn whilst keeping Western comforts. KAI invites one to discover the multifaceted aspects of Japan through natural hot springs, exploration of local arts and entertainment, and classic Kaiseki-style course meals using local and seasonal flavors. Experience Washoku, Japanese cuisine, presented on carefully selected ceramics for full exposure to culinary sensations.

About Hoshino Resorts
Hoshino Resorts was first established as a Japanese inn/ryokan in 1914 in Karuizawa in Nagano Prefecture before it began the operation of other resorts in Japan. Today, it has evolved into a highly influential hotel management company and is run by 4th-generation family member Yoshiharu Hoshino. Providing a unique experience focused on the local charms of each destination and a high level of omotenashi, Japanese-style hospitality, the company has expanded rapidly out of Karuizawa since 2001 and now operates more than 60 accommodations both in and outside Japan with one of the following categories: luxury hotel brand “HOSHINOYA,” hot spring ryokan brand “KAI,” countryside resort hotel brand “RISONARE,” city tourism hotel brand “OMO,” free-spirited hotel brand “BEB,” or other unique lodgings.


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