Svartifoss (Icelandic for “black waterfall”) is a waterfall in Skaftafell in Vatnajökull National Park in Iceland and is one of the most popular sights in the park. It is surrounded by dark lava columns, which gave rise to its name.

The waterfall tumbles down 20 meters (80 ft) over a cliff, which is bordered on both sides by tall black basalt columns. It resembles the pipes of a giant organ, which is where the waterfall gets its name.

The base of this waterfall is famous for its sharp rocks. New hexagonal column sections break off faster than the falling water can wear down the edges.

This wonder of natural architecture inspired the design of both Iceland’s National Theatre and the Hallgrimskirkja church in Reykjavik. The hexagonal columns form inside a lava flow which then cools extremely slowly, giving rise to crystallization. These lava formations are similar to those at the famous Giant’s Causeway in Northern Ireland and on the island of Staffa in Scotland.

Best period to visit Svartifoss and other waterfalls in Iceland is in summertime. Then all roads are open and temperatures are acceptable and also good for melting snow and ice off of the glaciers.