Iceland volcano — Reykjanes eruptions, Grindavík and the Blue Lagoon
The Sundhnúkur eruption series
Between December 2023 and August 2025, nine short but intense eruptions broke out along the Sundhnúkur crater row north of Grindavík. The most recent began on 16 July 2025 and ended on 5 August 2025. Before the eruptions, Grindavík, the campsite and the Blue Lagoon were evacuated.
The Icelandic Meteorological Office (IMO) reports that the ground beneath Svartsengi is still rising and magma is still accumulating — about 29 million cubic metres since the previous eruption, according to August 2026 calculations. The most likely scenario is another magma intrusion and eruption along the same crater row.
How much warning is there
The date cannot be predicted. In previous eruptions, the time from the first seismic signals to lava breaking the surface ranged from about 20 minutes to just over four hours. That is why authorities close the area early and why evacuating the Blue Lagoon has become routine.
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Flights and travel in Iceland
Fissure eruptions on Reykjanes produce lava rather than tall ash columns. During the eruptions so far, Keflavík airport kept operating and Reykjavík and the Ring Road were not threatened. This is a different kind of event from the 2010 Eyjafjallajökull eruption that grounded flights across Europe.
The real risks for visitors are volcanic gases collecting in hollows, ground cracks in Grindavík and fresh lava that looks solid on top. Walk on lava fields only along paths the authorities have opened.
Wind and weather — Europe
Wind direction and speed decide which way a fire runs. Switch the layer to temperature or humidity to judge the risk.
Strong wind, temperatures above 35 °C and humidity below 30% together are the conditions in which fire spreads fastest.
Where to check official updates
Official sources are the IMO website (vedur.is) with its hazard map and safetravel.is for current road and site closures. In an emergency call 112. More on volcanoes and travel in our other hazards section.