Volcanic activity on the Reykjanes Peninsula

The Reykjanes Peninsula in southwest Iceland is one of the most geologically fascinating places on Earth, where the forces that shaped Iceland are still at work. Since 2021, the peninsula has seen twelve fissure eruptions, all confined to a limited area. At the time of writing, no eruption is underway. Here's what's happened, how the area is monitored and how Blue Lagoon welcomes guests safely.

Why is the Reykjanes Peninsula volcanically active?

The Reykjanes Peninsula is volcanically active because it sits on the Mid-Atlantic Ridge, where the North American and Eurasian tectonic plates are pulling apart. The plates separate by about 2.5 centimeters (1 inch) per year, stretching and cracking the Earth's crust. Magma rises through these cracks, causing the earthquakes, fissure eruptions and geothermal activity the region is known for.

Reykjanes volcanic periods: From settlement to today

Volcanic activity on the peninsula follows a natural rhythm of active and quiet periods:

• Late 9th century onward: Eruptions on the peninsula have been recorded since Iceland was settled.

• 1210–1240: The Reykjanes Fires ended the last active period, forming some of the largest lava fields in Iceland's recorded history.

• 2021: After roughly 800 years of quiet, a new active period began with the Fagradalsfjall eruption.

Volcanoes in Icelandic landscape and folklore

These natural events are far more than scientific curiosities. For more than a thousand years, they have shaped the land Icelanders live on and the stories they tell about it. Moss-covered lava fields, steaming vents and black-sand shores have inspired generations of folklore. Gunnuhver, one of the peninsula's most powerful hot springs, is said to take its name from a restless ghost who was lured into its boiling waters. Today, the same forces make Reykjanes a place where visitors can see the Earth still being formed, and a rich subject for historical and geological study alike. For in-depth geological background, see the Smithsonian Global Volcanism Program.

Current volcanic activity on the Reykjanes Peninsula

Scientists often refer to the current era as the "New Reykjanes Fires," after a similar period of activity in the 13th century. Since 2021, the peninsula has seen twelve eruptions: three in the Fagradalsfjall area and nine along the Sundhnúkur crater row north of Grindavík.

2021–2023: The Fagradalsfjall eruptions

The current era began in March 2021, when the Fagradalsfjall volcano erupted after a period of earthquake activity. Two more eruptions followed nearby. In August 2022, lava fountains rose along a 300-meter fissure in the Meradalir Valley, producing 10.6 million cubic meters of lava within its first two weeks. In July 2023, the Litli-Hrútur eruption released volcanic gas close to the eruption site, but did not significantly affect nearby communities or flights. All three took place in remote valleys, away from towns and infrastructure, and drew visitors from around the world.

Late 2023: Activity shifts to Svartsengi

In late October 2023, earthquake activity began in the Svartsengi volcanic system, the area around Blue Lagoon and the Svartsengi geothermal power plant. In November, more than 1,000 earthquakes were recorded in 24 hours near Grindavík. On November 10, a magma intrusion formed beneath the town, and residents were evacuated as a precaution. The first eruption in the Sundhnúkur series followed on December 18, 2023: a fissure eruption along the Sundhnúkur crater row, near the mountains Sýlingarfell and Hagafell.

How the Sundhnúkur eruptions work

Magma collects in a reservoir about 4–5 km (2.5–3 miles) beneath Svartsengi, and the ground slowly rises as it fills. Over time, magma can move sideways into a dike, a vertical sheet of magma, beneath the Sundhnúkur crater row. Sometimes it reaches the surface as a fissure eruption. These eruptions typically begin with lava fountains along a fissure several kilometers long. They weaken within hours or days, often ending with a single active crater. They mainly produce lava and volcanic gas, with little ash.

Timeline of the Sundhnúkur eruptions (2023–2025)

Between December 2023 and August 2025, nine eruptions occurred along the Sundhnúkur crater row. Each was confined to a limited area and closely managed by Icelandic authorities.

• December 18–21, 2023 (~3 days): The first eruption of the series.

• January 14–16, 2024 (~2 days): A fissure opened just north of Grindavík. Lava reached the town's edge, causing property damage.

• February 8–9, 2024 (~1.5 days): An eruption north of Sýlingarfell. Lava crossed Grindavíkurvegur (Route 43) and a hot-water pipeline from Svartsengi, temporarily interrupting heating on the peninsula until repairs were completed within days.

• March 16 – May 9, 2024 (~54 days): The longest eruption of the series.

• May 29 – June 22, 2024 (~24 days): Protective barriers diverted the lava. Two of the three main roads into Grindavík were temporarily closed.

• August 22 – September 5, 2024 (~14 days): The largest eruption by volume, with about 61 million m³ of lava.

• November 20 – December 8, 2024 (~18 days): Protective barriers kept lava away from the Blue Lagoon site, though it reached the parking area.

• April 1, 2025 (~7 hours): The shortest and smallest eruption of the series.

• July 16 – August 5, 2025 (~20 days): Volcanic haze was noticeable across parts of Iceland.

How is volcanic activity monitored?

At the time of writing, there is no eruption on the Reykjanes Peninsula. The area remains geologically active and is one of the most closely monitored volcanic regions in the world. The Icelandic Meteorological Office (IMO) tracks earthquakes, ground movement and gas levels around the clock, using a dense network of seismic sensors, GPS stations and satellite data. Before each of the recent eruptions, these instruments picked up clear warning signs, allowing authorities to respond quickly with well-rehearsed plans. The IMO works closely with the Department of Civil Protection and Emergency Management, and Blue Lagoon is in continuous contact with both. For the latest information from Blue Lagoon, visit our volcanic activity updates page.

Does volcanic activity affect travel in Iceland?

Volcanic activity on the Reykjanes Peninsula stays within a limited area. Reykjavík has not been physically affected, Keflavík International Airport has remained open throughout, and travel across Iceland continues as normal. Because these eruptions produce mainly lava and gas rather than large ash clouds, they have not caused significant disruption to flights.

Helpful resources:

Icelandic Meteorological Office: Updates on weather and natural conditions across Iceland.

SafeTravel: Practical travel and safety advice for exploring Iceland.

Blue Lagoon opening hours: Plan your visit and find the best time to come.

Latest updates from Blue Lagoon: Current information about volcanic activity and our operations.

As anywhere in Iceland's natural landscapes, we recommend following the guidance of local authorities when exploring the outdoors.

Why the Reykjanes Peninsula matters for science, energy and nature

The Reykjanes Peninsula is one of the few places on Earth where a mid-ocean ridge rises above sea level. Its seismic and volcanic activity makes it a valuable resource for science, a cornerstone of Iceland's energy and home to some of the country's best-known natural wonders.

A living laboratory for science

The seismic activity on the Reykjanes Peninsula serves as a valuable resource for scientific research, providing a live laboratory to study tectonic plate movements, magma dynamics and the mechanisms underlying earthquakes. Data from seismic sensors, satellite imagery and ground observations enhance our understanding of these processes, contributing to improved predictive models for both eruptions and earthquakes, in Iceland and beyond.

Geothermal energy for everyday life

Beyond the scientific community, this activity plays an important role in society. The geothermal energy derived from the region's volcanism is a cornerstone of Iceland's energy strategy, offering a sustainable resource for heating and electricity. On the peninsula, the Svartsengi power plant supplies heating and hot water to local communities, and it is also where Blue Lagoon's geothermal seawater comes from. Read more about geothermal water in Iceland.

Natural wonders and sustainable tourism

The peninsula's geothermal hot springs, including the famous geothermal spa at Blue Lagoon Iceland, are not only natural wonders but also key attractions in Iceland, promoting sustainable tourism. The designation of the area as the Reykjanes UNESCO Global Geopark highlights the importance of the sustainable management of natural resources. Careful monitoring by the Icelandic Meteorological Office (IMO), which issues warnings and provides information to ensure public safety, helps visitors enjoy the area responsibly.

How Blue Lagoon ensures the safety of guests

The safety of our guests and staff is always our highest priority. The lagoon, hotels, and spa facilities at Blue Lagoon have been protected throughout recent volcanic activity. When needed, precautionary evacuations have been carried out, followed by well-coordinated reopenings, a process for which we are thoroughly prepared and ready to implement whenever necessary.

Advanced monitoring and close coordination with the Icelandic Meteorological Office (IMO) and the Department of Civil Protection and Emergency Management enable Blue Lagoon to anticipate and respond promptly to geological activity. Comprehensive safety protocols and well-practiced evacuation plans reflect our commitment to operational resilience and the wellbeing of both guests and staff.

Protective barriers on the Reykjanes Peninsula

Specialized protective barriers have been constructed across the area. These barriers are engineered to safeguard vital infrastructure by redirecting potential lava flows, and they are based on expert analysis of various volcanic eruption scenarios. During recent eruptions, they have successfully diverted lava away from key sites, including the Svartsengi power plant and the town of Grindavík.

A dynamic showcase of Earth's natural forces

The Reykjanes Peninsula is a dynamic showcase of Earth's geological forces at work. Its history and ongoing activity offer rare insight into the shifting of tectonic plates and how these deep movements shape the land above. The lessons learned here have far-reaching value, from improving our ability to forecast geological events to using geothermal energy for sustainable development.

This interaction between natural forces and human innovation reflects our ongoing commitment to living in harmony with our planet's ever-changing nature. It's about finding the right balance between appreciating the peninsula's extraordinary beauty and ensuring the safety and sustainability of how we experience it.

Frequently asked questions

What characterizes the eruptions in the Reykjanes volcanic systems?

Eruptions are characterized by localized lava fountaining on eruptive fissures and craters, producing lava fields with minimal ash.

When did the current volcanic unrest in the region start?

The current volcanic era began with the Fagradalsfjall eruption in March 2021. Activity in the Svartsengi area, near Grindavík, began in late October 2023, followed by a series of eruptions along the Sundhnúkur crater row.

What does the volcanic unrest involve?

It involves repeated patterns of ground uplift due to magma inflow and subsidence due to magma outflow forming magmatic dike intrusions.

Are future eruptions likely in the region?

Yes, with the continued inflow of magma, repeated dike intrusions and possible eruptions are likely.

How is volcanic activity monitored?

The Icelandic Meteorological Office tracks earthquakes, ground movement and gas levels around the clock, using seismic sensors, GPS stations and satellite data. These instruments have detected warning signs before each of the recent eruptions.

Have any measures been taken to mitigate the risk of lava flow?

Yes. Specialized lava barriers have been built around the Svartsengi power plant area and north of Grindavík. During recent eruptions, they have successfully diverted lava away from key infrastructure.

Is it safe to visit Blue Lagoon?

Yes. The safety of guests and staff is Blue Lagoon's highest priority. We work in close coordination with the Icelandic Meteorological Office and Civil Protection, and comprehensive safety protocols and well-practiced plans are in place.

Does volcanic activity affect flights to Iceland?

The recent eruptions have not caused significant flight disruptions. Keflavík International Airport has remained open, as these eruptions produce mainly lava and gas rather than large ash clouds.

Does volcanic activity affect travel elsewhere in Iceland?

No. Activity has stayed within a limited area of the Reykjanes Peninsula. Reykjavík has not been physically affected, and travel across Iceland continues as normal.