One of the scariest places in Iceland is Dimmuborgir, a collapsed lava tube formed by a lava lake near Mývatn, a large lake in the north of Iceland. In Icelandic folklore, the area is said to connect earth to the infernal regions. Basically, it’s a gate to hell formed by lake of fire.

Within the Nordic Christian lore, dimmuborgir is the place where Satan landed when he was cast out of heaven. The formations and shapes in the area are known in Norwegian as, “Helvetes katakomber,” which translates to “The Catacombs of Hell.”

It’s one of the most visited natural formations in Iceland and has been featured in HBO’s Game Of Thrones as an area far, far beyond the wall.

As the holidays approach, it takes on another meaning to Icelanders. It’s the home of Grýla, a troll, her third husband Leppalúði, and her sons, the Yule Lads, the 13 elves of Christmas (an Icelandic version of Santa Clauses, only more mischievous).