Kárahnjúkar Dam

Karahnjukar Dam is one of Iceland's largest hydropower structures and a central part of the Karahnjukar hydropower development in the highlands north of Vatnajokull. The dam blocks the Jokulsa a Bru river at Fremri Karahnjukur and, together with Desjara Dam and Saudardalur Dam, forms the Halslon reservoir.

The dam is 198 metres high and about 700 metres long. It is a concrete-faced rockfill dam and is the highest dam of its type in Europe. Water from Halslon is carried through long underground tunnels to Fljotsdalur Power Station.

When Halslon fills in late summer, water may flow over the spillway near the western end of the dam and form the Hverfandi waterfall into Hafrahvammagljufur canyon.