Situated in the Ódáðahraun lava field, Trölladyngja (Icelandic pronunciation: [ˈtʰrœtlaˌtiɲca] ⓘ) is the biggest of the Icelandic shield volcanoes,[3] reaching a height of 1,460 metres (4,790 ft) above sea level, and rising almost 600 m (2,000 ft) above the surrounding desert and lava fields.

[4] It is about 10 km (6.2 mi)in diameter and its inclination is 4 to 5° in the lower slopes, but 6 to 8° at higher elevations.

[6] This includes a Bárðarbunga volcanic system origin lava field branch, that possibly erupted from the fissure swarm south of Trölladyngja before 8000 years ago, that reached the valley of Bárðardalur, a distance of roughly 100 km (62 mi) and quite close to the northern Iceland sea coast.

[2] The shield volcano itself is situated north of latitude 64.7° where the strike direction of the fissure swarms formed in the last 10 million years and the 2014 dyke intrusion from Bárðarbunga towards the north have the orientation of the Northern volcanic zone.

[7] The Bárðarbunga central volcano to the south is definitely in the Eastern volcanic zone.