It may not have an easily identifiable conical silhouette, but Krafla asserts itself as the region's most active volcano. Its highest point (818m) is the mountain of the same name, which stands guard over Víti crater lake. Located in a 90km fracture zone, it stretches over some 10km. An immense magma chamber lies less than 3km deep. When the pressure increases, the ground lifts up and the magma seeps out of the earth, as happened in 1724-1729 and 1975-1984.