Tourists encounter an incredibly colorful world in the depths.
Thrihnukagig (Icelandic writing Þríhnúkagígur) is a sleeping volcano in Iceland, not far from the capital Reykjavik. The volcano of 3270 square meters and 213 meters deep has not broken out in the last 4,000 years. It was discovered only in 1974 and opened in 2012 before the tourists.
It is the only volcano in the world where visitors can descend into the empty nucleus chamber with an elevator. Tourists are welcomed by a colorful world created by the molten, then solidified rock.