Dimmuborgir is a large area of unusually shaped lava fields east of Mývatn. The area is composed of various volcanic caves and rock formations. It is one of the most popular natural tourist attractions in northern Iceland. According to folklore, Dimmuborgir is also the home of a famous troll named Grýla and her third husband Leppalúði. Game of Throne reference: This is where the wildlings set up the camp in season 3 north of the wall. It can also be seen when Ygritte steals Jon's sword and gets him into the cave.
One of several caves at the Dimmuborgir Lava Field near Lake Mývatn in North Iceland
Located among the bizarre lava formations of Dimmuborgir (Dark Castles) in the Lake Myvatn area, the unique Kirkjan (the Church) formations resemble the interior of a Gothic cathedral with a three meter (16 feet) hole running through it.