Þríhnúkagígur

Þríhnúkagígur is a dormant volcano in the volcanic system of Brennisteinsfjöll near Reykjavík, Iceland. Covering a 3,270 square metres (35,200 sq ft) area and a depth of 213 meters (699 ft), it has not erupted in the past 4000 years.

The landscape around volcanic areas looks stark. Black rock, steam vents, the smell of sulfur. Another planet.

Covering a 3,270 square metres (35,200 sq ft) area and a depth of 213 meters (699 ft), it has not erupted in the past 4000 years. It was discovered in 1974 by cave explorer Árni B. Stefánsson, and opened for tourism in 2012.

The terrain can be sharp and uneven. Good hiking boots aren't optional, they're essential.