Grábrók crater rises about 170 meters above the ground and is easily accessible via a footpath. It’s quite steep, so timber steps have been built on part of it to make the hike easier.
A brisk walk from the parking lot to the top of the crater and back again takes about 40 minutes. Once at the top you have an incredible view of the Borgarfjörður country-side and the encircling mountains.
The crater was formed about 3000 years ago in a fissure eruption and is interesting geologically because of the dramatic way the volcanoes have shaped the rock on the ground.