As
per the official estimates you could easily fit the New York’s Statue of Liberty or Reykjavik’s dominant Hallgrimskirkja Church inside this volcano chamber!
Thrihnukagigur (Þríhnúkagígur) is a dormant volcano southeast of Reykjavík, famous for its huge, empty magma chamber. It is the only magma chamber in the world that can be entered. Its depth is 213 meters (699 feet). Interestingly, the chamber was not discovered until 1974, and the find became a worldwide discovery. After all, volcanologists had never seen anything like it before. Why?
Several thousand years ago, Thrihnukagigur was a normal volcano in the Bláfjöll (Blue Mountains) range. However, its last eruption, nearly 2,000 years ago, had some very unusual consequences. Under normal conditions, after an eruption, a volcano’s magma chamber usually remains full of lava until the next eruption. If, on the other hand, the magma chamber is emptied, it is either ‘plugged’ from the top and surrounded by thick rock walls, or the volcano’s crater simply collapses under its own weight. However, to the scientists’ surprise, neither of these things happened at Thrihnukagigur. It is believed that the fissure beneath the chamber drained all the remaining lava, leaving behind a huge empty chamber.
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per the official estimates you could easily fit the New York’s Statue of Liberty or Reykjavik’s dominant Hallgrimskirkja Church inside this volcano chamber!
The chamber’s popularity is due not only to the unusual origins of the place, but also to the amazing colors inside. Mineral deposits color the walls with vibrant shades of red, yellow, green and blue.
Thrihnukagigur – tips and practical information
- In 2012 the rift was opened to tourism, but you can’t visit it on your own, only with a guide. Book your visit here: Thrihnukagigur: full-day tour from Reykjavik (6 hours, approx. $340/person)
- Tours take place only in the summer, start from Reykjavik, last almost a full day in total (about 6 hours, of which less than 1 hour inside the volcano) and are quite expensive: 47.000 ISK per adult person is just under $340 (2023). Children under 12 receive a 50% discount. Children under 8 are not taken on the tour.
- Getting to Þríhnúkagígur requires a bit of a hike – the bus parking lot is about 3.5 km / 2.2 miles away from the crater. So it’s about a 45 to 60-minute hike. Good physical condition is therefore welcome. As is preparation for various weather conditions. However, the organizer provides all the necessary caving equipment.
- You get to the magma chamber itself by a mine-like elevator;
If
you want to see similar scenery (although it’s not quite the same), you can take a trip to Vidgelmir Cave or Vatnshellir Cave at much lower prices, or visit the Surtshellir cave completely free. But these are ‘just’ lava tubes, whereas Thrihnukagigur is an actual volcano chamber.
How to get to Thrihnukagigur
To get to Thrihnukagigur from Reykjavik, you need to take road 49 south, and then near Blafjallavegur, turn onto road 417. However, without a purchased tour, you can only see the surface and the entrance to the volcano. Thus, it does not make much sense.
You have to buy a place on an official tour to get inside the volcano and these tours start from Reykjavik, so it doesn’t make a lot of sense to try and go visit the place on your own.
