Explore Reykjahlíð

Grjótagjá is a small lava cave with a geothermal pool, on a fissure of the plate boundary about 2 km south-east of Reykjahlíð by Lake Mývatn. It was a bathing place until the Krafla fires of 1975–84 heated the water to about 60 °C. The cave is on private land and bathing is not allowed; visitors look in from the entrance and walk along the rift above.

Hverir, also called Hverarönd, is a high-temperature geothermal field at the foot of Námafjall, east of Reykjahlíð and Lake Mývatn. Steaming fumaroles, boiling mud pots and sulphur deposits colour the ground yellow, grey and red, and roped paths lead between them; the smell of hydrogen sulphide is strong.

Hverfjall, also called Hverfell, is a tephra ring volcano east of Lake Mývatn that formed in an eruption about 2,500 years ago. Its black crater is roughly 1 km across. Two marked paths, from the north-west and from the south, lead up to the rim, and walking on any other route is forbidden.

Dimmuborgir is an area of lava pillars, arches and caves east of Lake Mývatn, formed about 2,300 years ago when a lava lake drained away and left behind hollow columns that had formed over boiling marshland. Marked trails of different lengths lead through the formations, including to the arched cave called Kirkjan.

Skútustaðagígar is a group of pseudocraters on the southern shore of Lake Mývatn, beside the farm and church of Skútustaðir. They formed about 2,300 years ago when lava flowed over the lake and its wetlands, and steam explosions built grassy cones with no vent beneath them. A walking path loops through the craters around the Stakhólstjörn pond.

Krafla is a volcanic caldera about 10 km wide north-east of Lake Mývatn, some 11 km from Reykjahlíð. Visitors walk to Víti, an explosion crater from the Mývatn fires of 1724–29 holding a green lake, and the Leirhnjúkur lava field, where trails cross steaming ground and lava from the Krafla fires of 1975–84.