Koyoi-no-Yuyado YUUZEN

All of the open-air guest baths in the eight detached guest rooms are 100% free-flowing hot spring water. The water is poured directly from the source into the bathtub, and any overflow is thrown down the drain. Though luxurious, the benefit of onsen kakenagashi (free-flowing hot spring) is that you can feel the hot spring components most. To continue to enjoy a clean bath in a bathtub with no chlorine or other disinfectants, it is generally considered necessary to have an output of 1 liter/minute of spring water per person. The hot spring at "Yuuzen" is a power pumped hot spring (drilled by boring) with its own source. The volume of water gushing out is 159 liters/minute. The maximum capacity of the facility is 22 people, which means that 7.2 liters/minute of hot spring water can be used per person by simple calculation. In other words, the inn boasts a very abundant hot spring water supply, which is more than 7.2 times the standard value. The higher the amount of hot spring water used per person, the more luxurious the hot spring can be, a figure that is sure to be a hit with hot spring lovers. The source temperature is 40°C. Depending on the outside temperature, the bath may be slightly lukewarm. A boiler may be used to heat the source only in the winter or when the temperature is low, but this rarely causes any loss of the hot spring components. A lukewarm hot spring bath is less stressful on the blood vessels because the rise in blood pressure during the bath is relatively slow. It is also good for taking a long bath. It is a unique way to use the open-air guest room baths, allowing you to enjoy the hot spring baths at your favorite time. The name of the spring quality is "Alkaline Simple Hot Spring", with a pH of 9.2. pH 7.5 or higher is considered weak alkaline, and pH 8.5 or higher is considered an alkaline hot spring. The definition of a "Simple Hot Spring" is a hot spring with less than 1000 mg of dissolved substances (excluding gaseous substances) per kilogram of spring water. Simple hot spring is a "gentle hot spring" with less stimulation because it contains less dissolved substances. In 2014, the "Guidelines for Mineral Spring Analysis Method," which are the rules for determining the name of spring quality, were revised, and for the first time, indications by spring quality were defined for simple hot springs as well. The indications unique to simple hot springs are Autonomic instability, Insomnia, and Depression. In other words, it acts on mental illnesses. These indications may be listed for other types of springs as well, but the simple hot spring's gentle nature (being a hypotonic hot spring) means that it can be bathed for long periods of time and is particularly effective for mental health. A characteristic of alkaline hot springs is that the skin feels melting when soaked. Since human skin is generally mildly acidic, touching a hot spring will dissolve dead skin cells and make the skin smooth to the touch. After the bath, the skin feels smooth and silky. The alkaline qualities of the hot spring are one of the conditions for what is called "Hot water for beauty". In addition, you notice the smell of sulfur when you soak in the hot water. Slightly, hydrogen sulfide ions and free hydrogen sulfide are contained in the source, giving it that specific sulfur smell, even though it is a simple hot spring. The "ankake" (starchy sauce) texture on the skin and the "sulfur aroma" make for a superb hot spring bath experience. Although the total dissolved substances do not reach the standard value (more than 1 g per 1 kg of spring water), the main component is bicarbonate ion. The bicarbonate ion is a component that emulsifies sebum and other skin secretions and removes them like soap. It leads to smooth skin after bathing. However, both alkaline components and bicarbonate ions thin the skin surface, making the skin easily dry after the bath. If you have dry skin, it is recommended that you apply moisturizing cream, etc. after taking a bath. The hot spring analysis report is notable for its metaboric acid content. Metaboric acid has a cleansing effect and is good for disinfecting the eyes and preventing "acne". The standard value for hot spring water is 5 mg/1 kg or more, but the hot spring water at this inn contains more than four times that amount (21.8 mg/1 kg). This component is also said to be effective for beautiful skin. In the hot spring analysis report of "Yuuzen", it can be found as metaboric acid ion in the column of anionic composition. According to the "Guidelines for Kosen Analysis Methods," the pH value of less than 9.2 is calculated as HBO₂ (metaboric acid), and the pH value of 9.2 or higher is calculated as BO₂- (metaboric acid ion). We hope you will fully enjoy the skin beautifying and relaxing effects of Yuuzen's abundant hot spring water in the tranquil atmosphere of the detached rooms.

"Koyoi-no-Yuyado Yuuzen" does not have "public baths for men and women", which are usually offered at most hot spring resorts. Instead, all guest rooms (8 rooms) have their own private open-air bath. The private open-air baths are spacious enough for four adults.
Moreover, each guest room is a detached room, so there is no need to leave the room except for meals. In short, Yuuzen is an inn that prioritizes privacy.
All rooms are set apart from each other, with no public baths for men and women. Instead, each room has its own spacious open-air bath, so that guests spend most of their time in their rooms, except for meals.
It should be noted that all eight rooms are Western-style rooms. From another angle, this means that staff will not bother you in your room after check-in (in the case of Japanese-style rooms, you will have to go to your room once to put out your bedding).
In addition, the room has an exquisite hot spring that makes you want to bathe in it as often as possible. We guess that some guests will spend most of their stay in the room, many of whom will spend most of their time in the room as naked as possible.
"Yuuzen" has a futuristic galvanized steel exterior, a space that emphasizes privacy by eliminating public facilities, cuisine that uses seasonal and local ingredients without being restricted to Japanese kaiseki cuisine, and an open-air guest bath where you can experience the gentle, lotion-like hot spring water... all of which make it a very attractive place to stay. The hotel has a lot to offer. Recently, the number of anniversary guests has been increasing. Spending time at an inn on an important day is proof of trust in the inn.
The concept of "an inn that is easy to access and yet offers an extraordinary experience"--this idea of the inn has spread, and we can expect further evolution of "Yuuzen" in the future.
Travel Journal