How Dimmuborgir Formed
Dimmuborgir formed approximately 2,300 years ago when lava flowed over a shallow lake or wetland. As the lava moved across the water, steam generated underneath forced its way upward through the still-molten rock, creating hollow columns and tubes. The outer surfaces of these columns cooled and solidified while the lava continued to flow and drain away beneath them, leaving the hardened shells standing independently. The result is a dense cluster of pillars, arches, and cave-like chambers spread across a roughly two-kilometre area.
The formations are sometimes described as pseudocraters or rootless vents, terms that refer to volcanic structures created by the interaction of lava and surface water rather than by direct eruption from a magma source below. Dimmuborgir is one of the largest and most varied examples of this type of formation in Iceland.
The Trail System
Dimmuborgir has a colour-coded trail network with three main loops, all starting from the main car park and visitor area.
The shortest loop, known as Kirkjuhringur, takes around 10 minutes and leads to Kirkjan, a natural lava arch that is one of the most visited formations on the site. The path is mostly flat and manageable for most visitors including families with children.
The medium loop takes around 45 minutes and covers a broader cross-section of the lava field, passing through narrower corridors between formations and offering a more complete picture of the site's scale and variety.
The long loop extends to around one and a half to two hours and takes visitors into less-trafficked sections of the lava field where the formations are denser and the sense of enclosure between the rock walls is more pronounced.
All trails are waymarked. The lava surface off the paths can be sharp and unstable, so staying on marked routes is important. Hiking boots with ankle support are recommended. The site is free to enter and the car park is free.
Folklore and Cultural Significance
Dimmuborgir features in Icelandic folklore as the home of the Yule Lads, thirteen mischievous figures from Icelandic Christmas tradition who descend from the mountains in the 13 nights leading up to Christmas Eve to leave gifts for children. Their mother, Grýla, is a figure from older Norse and Icelandic tradition associated with the mountains and caves of the north. The location of Dimmuborgir, with its cave-like chambers and dramatic formations, made it a natural setting for these stories in the popular imagination.
The site was also used as a filming location for the third season of Game of Thrones, standing in for the wildling camp beyond the Wall. The production choice reflects how closely the landscape resembles a fantasy setting without any modification.
Visiting Dimmuborgir
Dimmuborgir is open year-round. In summer the extended daylight hours allow visits at any time, and the site is at its most accessible between June and August when all trails are dry and the surrounding vegetation is in full growth. In winter the formations take on a different character under snow, with the contrast between dark basalt and white ground emphasising the shapes of the columns and arches. Some trails may be icy in winter and care is needed underfoot.
The site has no food or drink facilities, so bringing your own refreshments is necessary. There are basic toilet facilities at the car park. Lake Mývatn and the Mývatn Nature Baths are both within 10 minutes by car, making Dimmuborgir straightforward to combine with a broader Mývatn day.
