A Mile-Long Gateway to Hell Opens Up in Iceland

A volcanic eruption in Southwestern Iceland forced the evacuation of a nearby town and the world-famous Blue Lagoon geothermal spa on Wednesday, July 16. Media images captured huge plumes of smoke and glowing lava flows spewing from an enormous crack in Earth’s surface roughly 30 miles (18.6 miles) southwest of Reykjavík.

This marks the twelfth eruption since volcanic activity reawakened in this region in 2021. The eruption began on the Reykjanes Peninsula’s Sundhnúkur crater row around 4 a.m. local time, according to the Icelandic Meteorological Office. An intense earthquake swarm—a sequence of small earthquakes with no distinct mainshock—preceded the eruption.

Just after 5 a.m., lava began flowing southeast from an eruptive fissure that stretched roughly 2,300 to 3,300 feet (700 to 1,000 meters) long. As of 12 p.m., the eruption was no longer contained to a single fissure, the Met Office said. The larger, main fissure at Sundhnúkur crater had grown to a length of 1.5 miles (2.4 kilometers), and a smaller, 1,600-foot-long (500-meter-long) fissure had opened up west of the volcano Fagradalsfjall.

Lava flows burst from an eruptive fissure on the Sundhnúkur crater row in Iceland  © Civil Protection Department of the National Police Commissioner

The Government of Iceland says this eruption is highly localized and poses no threat to infrastructure, tourist attractions, or air traffic, but it does pose certain health hazards. Just before 9 a.m., the Met Office reported “witch’s hair” drifting in the wind. These are fine glass fibers that form when lava droplets rapidly cool and stretch. Because they can cause skin and eye irritation, officials advised locals to take precautions when outdoors near the eruption site. In Reykjanesbær, home to roughly 20,000 residents, officials also detected high levels of volcanic gases. These pollutants can irritate the respiratory system, but levels were decreasing around 9 a.m., according to the Met Office.

Officials said the eruption poses no risk to nearby communities, but they evacuated the town of Grindavík in an “abundance of caution” © Civil Protection Department of the National Police Commissioner

In an abundance of caution, officials ordered evacuations for the nearby town of Grindavík and the Blue Lagoon. Prior to 2023, Grindavík was home to nearly 4,000 residents, but its population shrunk significantly in recent years due to heightened volcanic activity in its locality. In 2021, powerful earthquakes began rumbling beneath this small town, generated by magma movement within the ​​Fagradalsfjall volcanic system. In March of that year, ​​Fagradalsfjall erupted for the first time in 800 years, putting an end to centuries of volcanic dormancy on Reykjanes Peninsula.

This is the twelfth eruption since volcanic activity reawakened in this region in 2021 © Civil Protection Department of the National Police Commissioner

Since 2023, Grindavík has faced repeated eruptions from Sundhnúkur, forcing residents to confront the reality of living atop an active volcanic zone. The town has remained mostly deserted since signs of an impending fissure eruption prompted an evacuation order in November 2023. The volcano finally erupted in December, causing structural damage to roads and buildings. Subsequent eruptions in 2024 caused further damage. By now, almost all residents have sold their houses to the state and left town. The desertion has contributed to a 4.4% population decline in Iceland’s Suðurnes region, according to Iceland Review.

It’s unlikely that Grindavík’s circumstances will improve anytime soon. Experts have said the eruptions in the area could recur for centuries, Reuters reports. So far, eruptions on the Reykjanes peninsula have not posed a threat to Reykjavik or disrupted air traffic in and out of Iceland. If that changes, these eruptions could have a national impact, taking a toll on Iceland’s booming tourism industry.