The Only Hotel in Iya Valley: Iyaonsen

Secluded Region – Iya Valley

Layered mountains extending in the distance. Iyaonsen is an excellent location for soaking up the beauty of Iya’s natural surroundings. A cable car takes guests down to the open-air bath at the bottom of the valley. Look out at the deep valley and the Iya River flowing below on the relaxing, approximately five-minute journey.

Hot Spring

Ride a cable car down to the open-air baths fed with hot spring water straight from the source. A cable car takes guests down to the open-air bath at the bottom of the valley.

Open-Air Baths


The chirping of little birds echoes from the depths of the forest, and the glossy green and jade of the river’s surface gently soothes your senses.

Open-Air Baths


Entrust yourbody to the clear spring water for a moment of bliss.Soft light plays on the water’s gently wavering surface.

Reservation Only Open-Air Bath


Beside the open-air bath for men and women, there is a private open-air bath that can be reserved for a fee.Here, guests can relax even more knowing that they will not be disturbed.

Large Bath Indoor Panorama Bath

The large bath is open 24 hours a day except for 1 hour between 10:30 AM and 11:30 AM when it is closed for cleaning.One for men and one for women.


Dine on the harvests of the season,grown right here in Iya.Wild mountain vegetables, sweetly fragrant river fish.Enjoy ingredients at their seasonal peaks.


7   H E L L S   O F   B E P P U


maximum of sea hell Among Beppu hell, if you are the colors of cobalt blue, is the beauty of the more unworthy is that hell.

Blue pond, because iron sulfate is dissolved is a component in the hot springs. In the park, has been cultivating the Amazon region of origin of the Victoria Amazonica and tropical water lilies using the hot springs, the flowering period of the Victoria Amazonica and tropical water lily, in early May – late November, is the morning is full bloom.


Blood Pond Hell in the oldest natural hell in Japan, if say a word “pond of red heat mud”. Hot underground, iron oxide produced caused the spontaneous chemical reactions under high pressure, a red hot mud containing magnesium oxide or the like is ejected from the formation, ponds one surface dyed red to deposit.



geyser waterspout hell, which is designated as a natural monument of Beppu.Exciting the ejection was hot water, there is spewing power about but about 30m are stopped by a roof.


pond in the Japanese garden of calm atmosphere, it has a white bluish. This, when ejection is transparent hot water, when fell into the pond, in order to vary pale by lower temperature and pressure. More Shiraike, tropical fish hall and pirarucu Museum, toward rough of prefecture designated important cultural property, Kunisaki towers and, and the like “two Honangado” the local art are on display.


had become tourist facilities of the attractions as the Meiji later “Mud Hell,” but was OPEN to be once closed new as “Onishi Mud Hell”. That’s right how the gray of heat mud boils became from that resembles a shaved head as called “Onishi Mud Hell”.

The location is next to the sea hell. In the facility, there is also a “foot bath”.


had become tourist facilities of the attractions as the Meiji later “Mud Hell,” but was OPEN to be once closed new as “Onishi Mud Hell”. That’s right how the gray of heat mud boils became from that resembles a shaved head as called “Onishi Mud Hell”. The location is next to the sea hell. In the facility, there is also a “foot bath”.


one stove Hell of Hells of Beppu is, gush Atsushi Izumi of 90 degrees of hot springs with fumaroles. The festival of the stove

Shrine of the patron god from ancient times, it had been cooked the Goku Midnight Eye rice in hell of fumaroles from its name. Kamado is hell there is a pond of a variety of hot water to 1-chome to 6-chome.


One of Japan’s best three hot springs


Located about 200 kilometers north-northwest of Tokyo, Kusatsu Onsen is a small town nestled in mountains where visitors can experience nature all year round.

Although its population is only around 7,000, it welcomes some three million tourists every year. Click here for detailed

information on Kusatsu Hot Spring, one Japan’s best three hot springs found in the center of the town of Kusatsu.


Acidic spring water containing sulfur, aluminum sulfate and chloride


Relief of neuralgia, muscular and arthritic pain, skin ailments, stiff shoulders, bruises, sprains, chronic fatigue, chronic women’s diseases, diabetes, high blood pressure and hardening of the arteries; promotion of general health and convalescence, etc.


The yubatake is the symbol of Kusatsu. Here, hot water from the spring’s origin gushes down wooden channels made from five-centimeter thick pinewood still containing large amounts of resin. Fine quality pinewood or Japanese cypress rich in resin is the optimum choice of material to continuously withstand acidic spring water. This is why many inns still have old, wooden bathtubs made of similar materials. Thus, the quality of Kusatsu’s spring water also serves to create a typically rustic hot spring atmosphere.


Kusatsu Onsen boasts the largest natural output of any hot spring in Japan.Trails of steam seen rising into the air all over the town enhance any traveler’s experience. Let’s take a look at this incredible amount of water that enables the continuous flow of the natural hot spring.Kusatsu Onsen is rightfully proud of both the quality and quantity of its waters.

Unmatched Quality and Quantity

In Kusatsu, more than 32,000 liters of spring water gush out every minute – the equivalent of some 230,000 barrels per day. The spring’s source is Mt. Shirane, an active volcano. This makes it possible for all Japanese style inns, hotels and spa facilities in Kusatsu Onsen to continuously provide their guests with spring water that doesn’t need to be reheated, diluted or otherwise adjusted. This lavish amount of water allows visitors to have a luxuriously sensational experience.

Fruits of the plentiful waters

Yubatake – “a field of hot water” – is the symbol of Kusatsu. Here, something called yu-no-hana (literally “sulfur flowers” or mineral salts) is formed when the massive quantities of spring water are exposed to the air. This natural bath salt is removed from wooden tubs four times a year while the water flow is temporarily halted. Carefully removed by hand, the bath salts are packaged in cone-shaped containers, whose annual production totals only seven to eight thousand.


At this traditional bathhouse, visitors can see demonstrations of yumomi and traditional dance done to a local folk song. A few members of the audience will be selected to try yumomi and will receive a certificate and complimentary gift. In the evening, traditional ”rakugo” comic storytelling performances are give here.

The hot springs in Kusatsu are put to various uses. In order to lower the temperature of the scalding hot Bandai hot spring to a temperature suited to bathing without diluting the water, a heat exchanger is used to pour cold tap water on the pipe through which the spring water flows. The tap water, which rises in temperature during the process, is then used to melt snow on roads and is supplied as hot water to Japanese style inns and private homes.

Another example is spring water that flows into the Yukawa River, which is neutralized with natural coal to maintain an environment suitable for fish. These are all facets of Kusatsu’s philosophy of “onsenism,” principles to maintain the quality of our hot springs.



Adventure into the ever-changing natural surroundings of Kusatsu in the winter!

Experience the untouched wonders of nature on this course, which gives participants a chance to enjoy the thrill of skiing as it was original done.


Situated on the west side of Kusatsu, this huge area has numerous wells from which hot water springs out to form a flowing river of hot water amongst large clouds of steam. Legend says a demon lives here, and visitors should not speak loudly or the demon will appear.




Kosenkaku’s commitment to fine cuisine begins with the selection of ingredients.

We carefully select each ingredient based on the season and its location of produce, in order to provide the finest dishes. We select ingredients not only from the local Arima region, but also from places throughout Hyogo Prefecture, including such places with abundant nature, such as Awajishima and Tajima.

The ingredients we procure are cooked by expert chefs and painstaking effort is made in the presentation of such dishes.


Kosenkaku’s master chef, Yasuhiro Morimoto was inaugurated as the President of the Hyogo Prefecture Cooking Association in July of 2017. He has served in key positions at renowned traditional Japanese restaurants, ryokans in the Kansai region,

and he joined Kosenkaku’s staff in 2007.

He has been in his current position since 2010. He has also jointly-published many books on the fundamental principles and techniques of Japanese cuisine.


Our carefully selected dishes enchant guests with

the changing colors of the seasons.

A Japanese spirit resides within the patterns, designs,

and colors of our dishes, which acts to further enhance

the beauty of each prepared dish.


Main Building, Annex Building, East Building Each guest room is unique and each of them was painstakingly designed and individually crafted at the time of the inn’s establishment. We want our guest rooms to be a space in which each guest can feel welcome to create some of their most pleasant memories. Each room acts as the foundation of our hospitality to our guests.

“While bathing, a private mini-garden can be viewed from all of our main building’s bathrooms. These rooms are suitable for a wide variety of uses including both family and group use.”

An Enhanced Sense of Peace and Comfort

“While bathing, a private mini-garden can be viewed from all of our main building’s bathrooms. These rooms are suitable for a wide variety of uses including both family and group use.”

The Hospitality of Blissful Silence

What is the purpose of your trip? Within the hectic pace of your daily life, we provide a place where pinned and strained nerves can loosen and be relaxed. At Kosenkaku, we hope to continue to provide guests with access to such a space. Amidst the otherworldly scenery you will encounter, you will find our high quality hot spring, and our famed cuisine. and our famed cuisine. We are prepared to receive you and those who are important to you as guests to our inn. We promise you a calm and peaceful holiday stay.

Two Hot Springs with Different Characteristics

“The Arima Onsen hot springs boasts more than 1,300 years of history and is one of Japan’s three oldest hot springs or “”kosen.” It is also one of Japan’s three most famed hot springs renowned for its water quality. Among Arima’s hot springs, Kosenkaku is one of the few ryokan (Japanese-style inn) that possesses its very own hot spring source. Thanks to this in-house hot spring source, the abundant supply of water allows for frequent replacement of the hot spring water to keep the water fresh.”

“Kinsen” (Golden Spring)

“The hot springs of Arima Onsen can be traced back to ancient times, and since antiquity, they were often referred to as the “”best host springs in the known world.”According to tradition, it is said that during the Nara period, Gyouki, a Japanese Buddhist priest, began to use the hot springs as a form of medical treatment.Visitors can find the two Kanji characters that combine to mean “”Miraculous Spring”” engraved into our Iwaburo bath.”

The Rustic Iwaburo Bath That Has Continued to Pour Fresh Hot Spring Water Since the Inn’s Establishment

“As an original hot spring with its very own hot spring source, our Iwaburo bath has not changed since its founding and it remains popular to this day.The tubs made of sculpted rock provide the bath with a dignified and refined atmosphere.Even today, fresh Kinsen hot spring water continues to pour into the Iwaburo bath from our bountiful hot spring source.”

The space fine view bath octagonal Buddhist temple which is culture in accord with trees

“Hakkakudo is hot spring bath that allows guests to enjoy a view of the garden with its changing colors of each season.Hakkakudo’s ceiling, pillars, and door frames are constructed entirely of Japanese Cypress wood, and the floor is made of black granite that is pleasant to the touch.From inside the entirely glass-walled bath,please enjoy our onsen while gazing at the forest that overflows with nature.”

July 2018