[…]The oldest of Finnish saunas were made as pits in the ground and date back to several thousand years ago. The oldest versions are estimated to bae from 7000 BCE. (2) Unfortunately, there is no written history of how the first sauna in Finland came to be. But there are remnants of saunas that were so-called “ground pit saunas” and were used during the stone age. (3)

Eventually the saunas were built outside, on top of the ground in small log cabins. They became very popular because of their versality. In their cold winters it would keep them warm, it allowed them to take care of basic hygiene and most importantly it was the perfect sterile environment to give birth.[…]

The Finnish Sauna — My Virtual World Trip


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Building a mobile / trailer Sauna — North and Beyond