Krafla and Leirhnjukur
Located east of Lake Mývatn, Dimmuborgir is a large area of unusually shaped lava fields; it is composed of various volcanic caves and rock formations.
The lava tubes that make the area so unique were formed by lava flows from the eruption of the Lúdentsborgir and Þrengslaborgir craters some 2,300 years ago. The walking path through Dimmuborgir is about 1 km or about 0.6 miles.
According to legend, 13 Yule lads (elves) live in Dimmuborgir, and 13 days before Christmas Eve, the Yule Lads, one after the other, come to town and put gifts into children shoes that have been placed on their windowsills.
Dimmuborgir means “dark cities” and, according to Icelandic folklore, the area is the connection between earth and hell and is thought to be where Satan landed when cast out from Heaven.