Grábrók is a crater in an area called Norðurárdalur.
Grábrók is a crater in an area called Norðurárdalur. The crater is the largest of three in a volcanic fissure, and is interesting geologically because of the dramatic way the volcanoes have shaped the rock on the ground. The lava her is thought to be approximately 3000 years old and extends over a wide area. Grábrók sits at the top of a small hill and is easily accessible via an easy footpath. From the top the views are fantastic, and well worth the short walk.