In December 2019, a series of earthquakes began to rattle western Iceland, between Keflavik, the nation’s only international airport, and the capital Reykjavik. The earthquake swarm indicated the re-awakening of the long dormant Reykjanes volcanic system, which had last erupted in 1240 — almost 800 years ago. Over the next months the swarm continued, accompanied by inflation (a slight increase in elevation of the Earth’s surface above an upwelling of magma). On March 19, 2021, the magma breached the surface, marking the beginning of the Fagradalsfjall eruption, which began as a series of lava fountains that soon coalesced into a single crater. Despite being close to Reykjavik, the lava flows didn’t reach any settlements or infrastructure. The initial eruption tapered off by September 18, followed by two more that lasted until August 2023.
A plume of gas and ash rises from Fagradalsfjall Volcano on July 11, 2023. Look closely, and you can see glowing lava flows. Also note how the plume creates its own cloud.
(Robert Simmon with data from Copernicus/Sentinel-2)
As the eruptions at Fagradalsfjall ebbed and flowed, a series of earthquake swarms just to the west indicated another magma intrusion beneath the Svartsengi volcanic system. Unlike the unpopulated volcanic cones of Fagradalsfjal, Svartsengi is the site of a geothermal power plant, the thermal pools of the Blue Lagoon, and the fishing village of Grindavík. On December 18, 2023, the Sundhnúkur crater row above Svartsengi erupted only 4 kilometers (2.5 miles) from Grindavík. While the first eruption spared the town & power plant, subsequent eruptions impacted both. Between December 18, 2023, and August 4, 2025, a total of 9 separate eruptions covered about 6.6 square kilometers (2.5 square miles) in fresh lava.
Grindavík, the Blue Lagoon, and the Svartsengi geothermal power plant. The light-brown ridgelines extending from the southwest (lower left) to the northeast (upper right) are remnants of the eruptions that occurred from 950 to 1240.
Satellite image collected on May 9, 2020.
(Robert Simmon with data from Copernicus/Sentinel-2)
Both Fagradalsfjall and Sundhnúkur are quiet at the moment (late June, 2026), but the Icelandic Met Office reports that magma continues to accumulate in the Svartsengi volcanic zone. Given that the last series of eruptions in the region lasted about 300 years, it’s a good bet that these eruptions aren’t over yet.