Selfoss is a waterfall on the river Jökulsá á Fjöllum in the north of Iceland. The river drops over a number of waterfalls over about 30 kilometres (19 mi) before flowing into Öxarfjörður, a bay of the Arctic Sea. Since the river originates as melt water from the glacierVatnajökull, flow varies depending on the season, the weather, and volcanic activity.Picture: Martin Falbisoner