In this photo you can see a path leading up the slope to the right of the waterfall. By walking up there you can get a good view over the surroundings and then you can continue walking because this is one of the ends of a very popular walks in Iceland.
The walk goes over a mountainsite which is calles Fimmvörðuháls and it takes you between the glaciers Mýrdalsjökull and Eyjafjallajökull. The other end is in Þórsmörk which is a kind of a oasis in the wilderness of the Icelandic moutainsites.