Dettifoss is a waterfall in Jökulsárgljúfur National Park of Northeast Iceland, not far from Mývatn. It is situated on the Jökulsá á Fjöllum river, which flows from the Vatnajökull glacier and collects water from a large area in Northeast Iceland. The falls are 100 m wide and have a drop of 44 m down to the Jökulsárgljúfur canyon. It is the largest waterfall in Europe in terms of volume discharge, having an average water flow of 200 m3/s.
The waterfall can only be reached by a rough road. On the west bank there are no facilities and the view on the waterfall is somewhat hindered by the waterfall's spray. On the east bank there is an information panel maintained by the staff of Vatnajökull National Park (Vatnajökulsþjóðgarður) and a maintained track to the best viewpoints.
The musical composition 'Dettifoss' (Op.57) by Jón Leifs is inspired by this waterfall.
