Images above on right were taken by Freysteinn Sigmundsson during the 1998 eruption of Grímsvötn
This system is about 62 miles (100 km) long and ~9 miles (15 km) wide. It is mostly covered with ice named Vatnajokull. The total volume of lava erupted from the Grimsvotn system is about 50-55 cubic km. Only about 19 cubic km of this lava is not covered by the ice. The system rises to the northeast from about 1000 ft (300 m) above sea level in the southwest.
It reaches its tallest point at Grímsvötn volcano. This volcano has a 35 sq km caldera. A high temperature hydrothermal area is located in this caldera. Grímsvötn has erupted 45 times.
The last major eruption of the volcano was in 2004.
Rope up with online National Geographic correspondent Ford Cochran and follow world-renowned volcanologist Haraldur Sigurdsson as he climbs, crawls, and paddles his way deep into the belly of this smoldering beast.
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