Grímsnes () is a fissure or crater row volcanic system located in South Iceland, a relatively small volcanic system located SE of Thingvallavatn lake east of an en echelon group of volcanic fields extending across the Reykjanes Peninsula. The elevation at its apex is 214 meters. Tephrochronology approximates the volcano's last eruption as 3500 BC. The individual volcanoes in the area include Kerið, a lake-filled volcanic crater. The Grímsneshraun lava-fields in the area cover a total of . The largest of these plains is the Seyðishólar-Kerhólahraun field which covers . Other sizeable plains include the Tjarnarhólahraun field at , the Kálfshólahraun field at and the Álftarhólshraun . The total volume of lava produced in the lava flows of Grímsnes has been estimated at See also Geography of Iceland List of lakes of Iceland List of volcanoes in Iceland Volcanism of Iceland External links Grímsnes in the Catalogue of Icelandic Volcanoes Volcano Live Volcanoes of Iceland Fissure vents Dormant volcanoes South Iceland Seismic Zone Volcanic systems of Iceland VEI-3 volcanoes