Mývatn is thirty minutes east of Laugar on the ring road, with a loop of stops around the lake. Start with the pseudo craters at Skútustaðir on the south shore, then visit Dimmuborgir, a field of black lava towers and arches with marked walks of half an hour to two hours. Beside it stands Hverfjall, a tephra crater whose rim takes about an hour to walk around.
East of the lake, the ground changes. At Hverir, beneath the Námafjall ridge, the earth boils and steams in mud pots and vents. A little further on, the Krafla road climbs to the crater lake Víti. Back towards the lake, finish the afternoon at the geothermal baths above the shore.
The lake takes its name from its midges. They do not bite, but they swarm on still, warm days in June or July. A head net from the shop is money well spent, and a breeze clears them.