The Finnish language carries indications of an early sauna culture. Words referring to the sauna and to taking sauna, such as sauna and related terms - kyly, loyly, and vihta - come down to us from a time when there was a common language in this wide area. This language evolved some 3,000 years ago, when it began to break away from its predecessor, early Proto Finnic. The words which are so significant with reference to sauna were thus known in the earlier Bronze Age (1500—900 B.C.) and so also, of course, was sauna itself. It may not have been an actual building — log building was not known at that time — but still as some kind of sweatbath. There are no archaeological sauna finds from the Bronze Age, but information can be gleaned through deduction. The kota with a pole structure was suitable for a nomadic life and was common form of habitation at that time. However, it did not lend itself well to use as a sauna because of its great height and arched form allowed the heat to escape upwards quickely through the opening at the top. Where portability of the home was not essential, a good shelter could be made in a dugout in a sand hill, the sides lined with thin saplings and covered with layers of bark and turf as was later the case with the log cabin. Significantly, this habitation could double as a place for sauna.
