Britannica AI Icon
Adding us as a Preferred Source tells Google you trust our content, so our articles show up more often in your Google Search, Discover feed, and AI Overviews.
verifiedCite
While every effort has been made to follow citation style rules, there may be some discrepancies. Please refer to the appropriate style manual or other sources if you have any questions.
Select Citation Style
Feedback
Corrections? Updates? Omissions? Let us know if you have suggestions to improve this article (requires login).
Thank you for your feedback

Our editors will review what you’ve submitted and determine whether to revise the article.

External Websites

Jökulsá á Fjöllum, river, northeastern Iceland, fed by the northern meltwaters of the Vatna Glacier in east-central Iceland; it flows northward for 128 miles (206 km) to Axar Fjord, an arm of the Greenland Sea. The river skirts the eastern margins of Ódádhahraun, an extensive lava field, and then tumbles over a series of falls, the largest of which (Dettifoss, 144 feet [44 m]) has the greatest hydroelectric potential on the island. The second longest of Iceland’s rivers, Jökulsá á Fjöllum has the largest drainage basin, 3,070 square miles (7,950 square km).

This article was most recently revised and updated by Adam Augustyn.
Discover the fascinating events that shaped the world, straight from our editors.
By clicking “Sign Up”, you consent to the Britannica Privacy Policy and Terms of Use.