The Loki-Fögrufjöll is a subglacial volcano under the Vatnajökull glacier. The subglacial volcano is found within the Bárðarbunga fissure volcanic system, but is outside the caldera of Bárðarbunga itself. Earthquake swarms associated with the volcano are separate in time and place from other swarms in the Bárðarbunga system. The fissure swarm extending south-west towards Torfajökull has not had recent earthquakes or erupted in the Holocene.