Svartifoss (Black Fall) is a waterfall in Skaftafell National Park in Iceland. It is surrounded by dark lava columns, which give rise to its name. The hexagonal columns were formed inside a lava flow which cooled extremely slowly, giving rise to crystallization.
The base of this waterfall is noteworthy for its sharp rocks. New hexagonal column sections break off faster than the falling water wears down the edges.
These basalt columns have provided inspiration for Icelandic architects, most visibly in the Hallgrímskirkja church in Reykjavík, and also the National Theatre.