OSTERIA SINCERITA has a hot-spring guardian.

Our natural hot spring delivers the gifted water to guests without any addition.

The source of the spring water reaches the baths at a temperature of approx 57°C, and water is added continuously to reach 42°C, the preferable temperature for guests to enter the baths at the lowest outside temperature in the next morning.

The hot-spring guardian first checks the weather forecast to see next day’s minimum temperature.
Based on the data, the temperature of the water is adjusted by opening the valve and adjusting the amount of spring water to be added.

The adjustment of the valve opening is essential for the outdoor Zao rock stone bath which faces to the south, the sun or to the north, when the conditions are different especially during summer.

It is said that oxidation and deterioration of the spring water begins the moment it comes into contact with the air.

Therefore, the spring water received from the ground is transported directly to each bath without coming into contact with the air to prevent oxidation.

In the hinoki baths in each room, the water is brought as close as possible to the surface of the bath to avoid contact with the air.

Please enjoy the “freshly-born from fountainhead”.

On the theme of meditation, the outdoor Zao rock stone bath and the tatami room are separated by a circular window, with a image of temple in Kamakura.

The tatami room is set up for meditation.
Enter the tatami room with a slight, as if you were entering a tea ceremony room through a circular window.

The light in the tatami-room illuminates the paper screen of the circular window.

Would you like to experience the personal moon light shadow by closing the window while soaking yourself in gift from mother earth?

Immerse yourself in this ultimate ’freshly-born from fountainhead’ hot spring from the ground, through hollowed-out the bottom of the bath without any exposure to the air.

We also situated two additional bathtubs: one with a water temperature of approximately 42 degrees Celsius and a bathtub with a water temperature of approx 15 degrees Celsius to enjoy contrast of hot and cold baths.

Contrast baths stimulate the blood vessels on your skin, causing them to contract and dilate, which is reported to relieve fatigue and rejuvenate the body.

Ideas for the circular window with contrasting hot and cold baths were recommended by Mr. Kundo Koyama/script writer.

湯道温心
The way of hot water is to warm the heart, the way is to master it.

We would like to extend our appreciation to Mr. Koyama for furnishing his calligraphy for this special bath room.