Leirhnjúkur is a volcanic area in the north of Iceland, near Myvatn, just off the Ring Road, with black and red lava fields, bubbling mud pools and volcanic craters. It is an amazing site. The last volcanic eruption took place in 1984 and some sections of the lava field still give off steam. Upon returning home I realized that I didn't explore the entire area. I guess I have to go back one day.