The river Rissbach has it's origin near the Eng Alp in the Alpine Park Karwendel. It runs after 26 km into the River Isar which runs through Lake Sylvenstein soon afterwards.
Standing on the bridge that crosses the river Rissbach at the famous Rissbach Gorge and marks the border between Austria and Germany. Under the bridge the Rissbach rumbles down the narrow gorge and falls down over a series of three drops. The walls are vertical and have deep undercuts.
See also this autumnal pic of the gorge taken from the other side of the bridge.