Trölladyngja

Situated in the Ódáðahraun lava field, Trölladyngja is the biggest of the Icelandic shield volcanoes, reaching a height of above sea level, and rising almost 600 metres above the surrounding desert and lava fields. It is about 10 kilometres in diameter and its inclination is 4 to 5° in the lower slopes, but 6 to 8° at higher elevations. Its oblong crater is about 1,200 to 1,500 metres in length, 500 metres broad, and about 100 metres deep. Most of its lava fields have flowed in a northerly direction, with one branch of it reaching the valley of Bárðardalur, a distance of roughly 100 km.