Skutustadagigar

The craters at Skutustadir look volcanic and are not: they formed when lava flowed over the wet ground and marshes at the edge of Myvatn, flashing the water to steam that blew out through the molten rock and threw up rings of scoria. They are pseudocraters, with no vent or conduit underneath, and this is one of the best studied groups of them anywhere - comparable structures have been used as a reference for similar-looking features photographed on Mars. The site has been protected since 1973 and sits inside the wider Myvatn conservation area. Two marked loops run through the craters and along the shore, half an hour and about an hour.

What you actually see

• Craters with no vent below - steam explosions, not eruptions.
• A reference site - studied and compared with formations imaged on Mars.
• Protected since 1973 - within the Myvatn conservation area.
• Two short loops - through the cones and along the lake shore.

When to go

May to September; walkable whenever the ground is clear. One to two hours.

Honest expectations

Midges at Myvatn are overwhelming on warm still days and a head net makes the difference; they do not bite but they are relentless. The craters are low and read better from the marked viewpoints than from among them. Paths are gravel and can be wet.

Nearby

Myvatn's shore road continues to Dimmuborgir and Hverfjall.