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(CNN) Everywhere you look at Santorini, it occurs to you that you are on a volcano. The lunar landscapes, the black and red beaches, the pebbles of solidified lava. The overwhelming beauty of the Greek island is the result of the area’s violent volcanic history.
Santorini is of course famous for its breathtaking crescent-shaped caldera, half of which is submerged, making it the only submerged caldera in the world. It was created by one of the largest known eruptions around 3,600 years ago. The explosion was so powerful that it wrecked the ancient city of Akrotiri in Santorini and dealt a fatal blow to the Minoan seafaring civilization, which had settled on the island at the time.
Today, Santorini, also known as Thira, is Greece’s premier romantic playground with luxurious villas and resorts offering pampered getaways for A-listers and dreamy settings for lavish weddings and photo shoots. The island’s steep volcanic cliffs, perched nearly 1,000 feet above sea level, create an impressive geological canvas with whitewashed houses balancing on the edge. No wonder it’s one of the most photographed places on the planet.
Each evening, the island comes to a screeching halt for the famous Santorini sunsets. The blue-and-white-domed village of Oia fills up as the golden hour approaches. As the sun begins to set behind the caldera cliffs, the sky transforms into a vivid display of red, orange and pink hues. Thousands of people gasp as the last rays disappear into the sea.
Few realize that an active volcano is hidden beneath the hypnotic kaleidoscope of colours.
Secrets of the deep
Santorini is part of the Hellenic Volcanic Arc, one of Europe’s most important volcanic fields which has seen over 100 eruptions in the last 400,000 years. The eastern Mediterranean’s most active and potentially dangerous underwater volcano, Kolumbo, is located five miles northeast of Santorini and is part of the same volcanic system.
Submerged in the Aegean Sea, Kolumbo has been silent for almost 400 years, but it doesn’t sleep. The last time it blew, in 1650, it killed 70 people and triggered a 40-foot tsunami. Strong earthquakes and aftershocks have been recorded, along with toxic gases and plumes of smoke.
Scientists know that Kolumbo’s explosion could cause serious damage. Some of the world’s largest oceanographic expeditions have visited it, and monitoring has increased over the past 20 years. One of the largest US research vessels, the deep-drilling vessel JOIDES Resolution, traveled to Santorini on its first mission in the Mediterranean between December 2022 and February 2023.
The formidable vessel has brought “an entire floating laboratory to the area,” says volcanologist and expedition co-chief Tim Druitt. Capable of drilling more than 8,000 meters (26,000 feet) below the surface of the sea, the researchers collected previously unreached sediments to try to piece together the history of volcanism in the area.
The findings – the first reports are expected later this year – should help scientists not only predict future eruptions but also reveal the behavior of other active volcanoes around the world that pose a threat to millions of people. who live in their vicinity. The links between earthquakes and volcanoes are also being studied.
Evi Nomikou, a geologist and oceanologist at the University of Athens, has been on every expedition to her native Santorini over the past 20 years. “We are gradually putting together a geopuzzle [showing] what parts they were [originally] earth, parts of which were water,” he says.
“If we can better understand past eruptions and their impact, we have a roadmap to better address future challenges.”
An extraterrestrial ocean
The JOIDES Resolution Expedition is not the first major study in the area. Nomikou says the long-studied extreme conditions found at Kolumbo led NASA to fund a groundbreaking expedition in 2019. “At the bottom of its crater is an extraterrestrial ocean with life forms that can be found on other planets.”
The hostile environment, with its active hydrothermal vents that spew hot water and minerals, served as an ideal testing ground for cutting-edge new technologies using autonomous underwater vehicles. NASA has tested submersibles that will one day hopefully explore alien oceans on the moons of Jupiter and Saturn.
Another recent study also uncovered a previously undetected magma chamber under Kolumbo. Scientists believe the chamber may also hold the key to understanding seismic activity in this region.
Smoking volcanoes and bubbling craters have also fired the imagination of Hollywood producers who chose Santorini as the opening location for the adrenaline-pumping 2003 Hollywood blockbuster ‘Lara Croft: Tomb Raider – The Cradle of Life’. Using the spectacular cliffs of Santorini as a backdrop, Angelina Jolie found herself in dangerous situations in mysterious waters as she searched for underwater treasure.
Jolie and then-husband Brad Pitt vacationed in Santorini after filming, and they’re not the only ones. The Kardashians, Lady Gaga and Shakira are among the celebrities who have splashed around in the crystal clear waters of Santorini. Every summer, mega yachts sail back and forth between Santorini and Greece’s other celebrity magnet, the party island of Mykonos, their VIP passengers revealing their exclusive surroundings in glitzy posts.
Hiking craters and hot springs
Brangelina’s romance may be over, but Lara Croft’s adventurous spirit lives on on tourist boat trips. They include a visit to the volcano of Nea Kameni: one of the five islands that form the volcanic complex of Santorini, and itself a national geological park.
“Nea Kameni last erupted in the 1950s,” says Marios Fytros, managing director of travel agency Santorini View. “Visitors love the thrill of hiking up to the crater of a volcano. It’s one of our most popular hikes.” The boat tours continue with a swim in the volcanic hot springs of the nearby island of Palea Kameni, followed by sundowners on the deck facing the cliffs of Santorini.
Another popular tour, to the magnificent Akrotiri archaeological site, serves as an understated reminder of volcanic strength. The thriving Bronze Age city was destroyed in the eruption 3,600 years ago, which spewed a nearly 20-mile-high column of ash and rock, burying the city. Some 1,700 years later, a similar disaster would destroy Pompeii.
After removing the ashes and lava, Akrotiri’s brightly colored frescoes are beautifully preserved today.
A boiling volcano
Due to its worldwide fame, Santorini has seen some of the largest tourism investment in the country. Hilton and Nobu are among the brands that have arrived on the island in recent years, and property prices are among the highest in Greece.
Yet geologists – who are closely monitoring Kolumbo – warn it is only a matter of time before a major eruption strikes again.
However, “time” in geological years can be extremely slow. So much so that one real estate agent on the island, who declined to be named, says “volcanic activity never enters the conversation” when selling a property.
When it explodes, Kolumbo is capable of producing an eruption column tens of miles high and is also liable to trigger a tsunami. The increase in activity about 10 years ago raised concerns, but it has since declined.
“If we start to see an increase in activity in Kolumbo then we need to stay alert,” Druitt says. “The good news is that volcanoes give a lot of warning.”
Meanwhile, in 2020, Greece’s civil protection agency unveiled a 185-page plan to deal with the consequences of a possible activation of the Santorini volcanic group.
Volcanic food and wine
In their daily lives, locals have little time to think about the volcano other than hiking. In summer, the island is full. Overtourism remains a major challenge as Santorini’s unique landform continues to draw crowds. Last year the International Union of Geological Sciences, in collaboration with UNESCO, included the Santorini Caldera in its first list of the top 100 geological World Heritage Sites.
Apart from hotels and restaurants, all the island’s businesses are related to the volcano. The locally produced cosmetics are rich in minerals and the premium food ingredients are grown in the unique terrain. There is a museum dedicated to the Santorini cherry tomato, produced under Protected Designation of Origin since 2006, and the island’s broad beans are considered the best in Greece.
Then there’s Santorini’s most famous export after tourism: wine. Islanders say that there is more wine than water on Santorini.
About a fifth of the nearly 30-square-mile island is taken up by vineyards, most of which I grow assyrtikoa native grape that produces fresh, dry and, not surprisingly, mineral white wines.
The traditional “cave” houses carved into volcanic rocks, called yposkafa, are prime nesting places for honeymoon couples looking for their dream vacation. But for Nomikou, who grew up in Santorini, it was Kolumbo who appeared in her childhood dreams.
“I was greatly influenced by the stories of my grandfather and great-grandfather. They reminded me of the small explosions in Nea Kameni,” she says.
“But they insisted that what to worry about is ‘what you can’t see.'”
“Gradually I realized there was another volcano, underwater. A more powerful, mysterious and dangerous volcano. It’s impossible to know if any of us will survive a major eruption but, at some point, there it will be one.”
One day Santorini could be buried again under a layer of ash. But for now – as visitors enjoy another breathtaking sunset over a glass of assyrtiko – the volcano is silent.