Subglacial lakes

Grímsvötn (; vötn = "waters", singular: ) is an active volcano with a (partially subglacial) fissure system located in Vatnajökull National Park, Iceland. The central volcano is completely subglacial and located under the northwestern side of the Vatnajökull ice cap. The subglacial caldera is at , at an elevation of . Beneath the caldera is the magma chamber of the Grímsvötn volcano.

lake under a glacier