Up in the hills north of Hverir, the area around the Krafla volcano has been intermittently erupting for the last three thousand years and shows no signs of cooling down yet. The access road runs north off the Ringroad, passing right under piping from Leirbotn power station on the way. The station harnesses steam vents to generate power; these are what you can hear roaring away like jet engines up on Krafla’s flanks. Krafla itself (818m) was last active in the 1720s during a period known as the Mývatn Fires, which began when the west side of Krafla exploded in 1724, forming a new crater named Viti (Hell). The road ends at a car park in front of Viti, now a deep, aquamarine crater lake on Krafla’s steep brown gravel slopes; a slippery track runs around the rim through atmospheric low cloud and plenty of real steam hissing out of bulging vents.