In Kiev, Ukraine, there is a place where anyone can come and bath, both in summer and in winter, in clear stream water. It is called "Kopanka". It is located in the Goloseevo woods. It was built and rebuilt by volunteers, first as a modest well, then more elaborate with wood. It is maintained by volunteers who understand the good of it. Those who want can contribute money or labor towards maintaining it.
It is not one spot, but there are several. The photos below are of the one I bath in.
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