karst spring blaue brunnen next to lake klontalersee in the valley of klontal

alpine ancient autumn background beautiful beauty blaue blue brunnen building canton cave clear ecology emerald environment erosion europe flowing forest glarus green karst klontal klontalersee lake landmark limestone moss mountain natural nature next outdoor outdoors park plant pool reflection river rock scenic scenics source spring stream summer switzerland tourism travel tree turquoise uav underground valley view water wild wood