The collision between Africa and Europe caused the formation of the Alps millions of years ago. Layers of rock were pushed on top of one another, folded and broken. Along the so-called “Glarus main thrust fault”, a line that can now be seen from afar, layers of rock that were 250-300 million years old were pushed together with much younger rocks that were 35-50 million years old. There is nowhere else where the traces of these tremendous forces are so visible as in the mountain landscape around Piz Sardona in the border region of the cantons of St. Gallen, Glarus and Grisons. The area has great value for schools and research. It is of great interest to hikers and nature lovers too. Natural Heritage since 2008.