The architects tell us this is one of the first mixed baths to be built in Japan since the 1940s, when they were made illegal.
The partially open-air complex is based on a series of interlocking circles, each of which houses a separate function such as changing, showering, mixed or single-sex bathing and indoor or outdoor bathing.
Constructed largely of timber, the baths have been named Moku Moku Yu - "moku" means wood while "moku moku" means steaming or boiling and "yu" means bath.
The cloudy quality of the water is due to nitrogen bubbles that are constantly pumped through the baths.
The baths, which formally open on 26 January 2007, can hold up to 40 people and are situated in the woods surrounding the Risonare hotel, which is also the location of KDA's famous Leaf Chapel.
Designed to host weddings, the chapel features a eyelid-shaped steel veil that rises at the end of each ceremony, allowing the wedding party to spill into the gardens thereby vacating the chapel for the next party.
Last year, Klein Dytham added a mirror-clad dining and party space at the hotel, called Brillare.
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