Very old savusauna. No chimney and not even much of structure to hold the rock in place.
Suomen Saunaseura ry: savusauna
Traditional savusauna, consisting of an open fire under piled rocks and no chimney. After many hours a vent in the roof is opened and the soot is swept off the benches. It is the oldest type of sauna, with only a handful still operating worldwide.
Finnish Sauna Kakslauttanen Hotel, Winter Tours to Finland
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