The waterfall Dettifoss is located in Vatnajökull National Park in Northeast Iceland, and reputed to be the most powerful waterfall in Europe. It is also the largest waterfall in Europe in terms of volume discharge, having an average water flow of 193 cubic meter per second. Its volume often increases, especially when the weather or volcanic activity prompts glacial melting on the Vatnajokull glacier icecap. The waterfall is so powerful that it makes the surrounding rocks vibrate, the vibrations can be felt by hand. Dettifoss 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 fall is 100 metres wide and have a drop of 45 metres down to the Jökulsárgljúfur canyon.