Reykjanesfólkvangur Reserve

The volatile geothermal field Austurengjar, about 2km south of Kleifarvatn, is often called Krýsuvík after the nearby abandoned farm. At Seltún, the main sight, boardwalks meander round a cluster of seething hot springs. The mud pots and steaming sulphuric solfataras (volcanic vents) shimmer with rainbow colours from the minerals in the earth.

Even by Icelandic standards, this area is prone to geological tantrums. The temperature below the surface is 200°C and the water is boiling as it emerges from the ground. A borehole was sunk here to provide energy for Hafnarfjörður during the 1990s, but it exploded without warning in 1999 and the project was abandoned.

There are bathrooms at the site.