Up on a freezing Icelandic mountain, the hot dogs are almost ready. David Benediktsson, a shipbuilder, grabs one between the tip of his thumb and index finger to avoid touching the rock that has served as a natural frying pan.

Three hours earlier, that rock was 1,200C lava and the newest part of Iceland, pouring from a volcano that has been erupting for four weeks now. “This is my second time,” Benediktsson, 38, says to explain his skills at the volcanic barbecue.

Eight craters now line a kilometre-long stretch of mountainside in the Geldinga valley. Geologists call the eruption “minor”, but for the people of Iceland it is a rare opportunity to see their volcanic landscape take shape. Never in 800 years has a volcano, big or small, erupted this close to the capital Reykjavik, which lies only 32km to the north. Instead of the Super Jeeps, snowmobiles or helicopters needed to reach previous eruptions, getting here requires only hiking boots. A shuttle bus runs every hour from the nearby town of Grindavik.

Volcanoes have always attracted people. Mount Vesuvius was a popular destination on aristocratic grand tours of the 17th and 18th century; Mount Fuji has a knot of restaurants on its flank; Etna has a cable car. But this is a more visceral form of volcano tourism — the rush to see an eruption in progress. And it is growing, here and around the world, fuelled by the jaw-dropping pictures and videos shared on social media.

At least 40,000 visits to the Geldinga eruption have been made so far, according to officials, and a van serving fish and chips has been stationed at the edge of the road where the path to the volcano begins. “I had to seize the opportunity,” says its owner, Johann Hallgrimsson. Icelanders hope the volcano will continue to be a draw once international tourism bounces back. “Even if the eruption stops today, this place of balmy lava will remain a must-see,” says Hallgrimsson.

Fresh snow dusts the mountain ridge above as I leave the fish and chip van to start the hike up. Descending tourists are notably chattier and gigglier than those trudging up. There are few apparent traffic rules — a teenager slides down from above, forcing me to sidestep. Most people, myself included, wear traditional lopapeysa woollen sweaters in varying colours.

Hikers watch the Geldinga valley eruption in late March

Up on the ridge, the final part of the route is determined by wind. “Never watch the volcano with the wind in your face,” explains Logi Sigurdsson, a search and rescue volunteer whose job is to “hold back people’s curiosity”. That could mean being exposed to volcanic gases, including potentially lethal levels of sulphur dioxide.

I figure there is safety in numbers and follow the crowd. After about an hour’s walking, the path ends at the northern tip of a lava field hundreds of metres wide. The latest fissure opened only the night before and a massive tongue of lava spreads like honey over the yellow grass. Someone throws a large snowball. Puff! Another hurls a rock and we watch as it slowly sinks into the lava.

About 100 people are there when I arrive, alternating their attention between the infant crater taking shape and the screens of their cameras for selfies. More search and rescue volunteers watch as the lava stream comes towards us in slow motion. When it seems likely to pass down a cliff and across the pathway, they gently advise me not to get trapped.

Earlier this month hundreds of hikers were evacuated from the area when a new fissure opened up. Scientists have since urged more caution: no more volleyball games beside the crater.

The risks of volcano tourism are real. In December 2019, 22 tourists and guides were killed and 25 injured when the White Island volcano in New Zealand erupted unexpectedly. Tour operators there are now facing prosecution for failing to ensure the safety of staff and visitors; the first hearing is due to take place in June.

Sitting astride the mid-Atlantic ridge, Iceland is one of the world’s most active volcanic regions and residents have a close, if ambivalent, relationship with volcanoes. In most houses, the heating and hot water comes from geothermal energy — the water of the Blue Lagoon, the spa that is Iceland’s biggest tourist attraction, is the outflow from the nearby Svartsengi power station. Babies are named after volcanoes (popular choices include Hekla and Katla), and Icelanders enjoy constantly speculating about the next eruption. But they also fear a disastrous outcome.

During this eruption, geophysicist Pall Einarsson has presented geological theories and explanations on primetime television, aided by complicated slides that would scare away viewers in most other countries. “Outside of Iceland geologists are considered nerds studying rocks. Not here,” says Einarsson, who is a mini-celebrity, like many of his colleagues. Every time a volcano erupts, enrolment numbers at his university department rise the following semester.

“The problem is people often expect us to predict the future,” he adds. “This eruption might last for years — or end tomorrow. We cannot know yet.”

The best-selling novel in Iceland right now is Eldarnir (The Fires) by Sigridur Hagalin Bjornsdottir. A weirdly prescient book published last year, it concerns a female geologist in Reykjavik who is battling an eruption on its outskirts. “The volcano waited for me to finish,” Bjornsdottir says.

Meanwhile, an eight-part Netflix series Katla, due to be shown this year, is likely to spur even greater fascination. It is set in the southern Icelandic town of Vik, one year into a violent eruption of Katla, one of the country’s largest volcanoes (and where a real eruption is long “overdue”).

At Geldinga valley, the visitors stand as close as they dare to the running lava; close enough to enjoy its warmth and excitement. “It is already the most photographed volcano in Iceland’s history,” says veteran photojournalist Ragnar Axelsson, who has documented every eruption in Iceland for the past 45 years.

He admires the glow in the twilight, snapping the occasional photograph with a bulky camera. “Volcano pictures are fun to take,” Axelsson says, “but, like a beautiful sunset, the images themselves are very different from the real experience.”

Egill Bjarnason is the author of ‘How Iceland Changed the World: The Big History of a Small Island’, to be published by Penguin next month

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