This is Glymsgil (canyon) and the waterfall Glymur. It is 198 metres high (650 feet). It is the second highest waterfall in Iceland. We hiked the canyon one spring night to get close to see the waterfall. It´s difficult and there have been accidents because of rocks falling into the canyon. We saw two rocks falling on our way. The canyon is over 200 metres high. Impressive but I can´t recommend it because of the danger.