A quintessential Mediterranean escape perched atop an active volcano

Santorini constantly reminds you of its volcanic roots. From the otherworldly landscapes to the black and red sandy beaches, and the pebbles made from solidified lava, the island’s stunning beauty is shaped by its fiery past.

Renowned for its striking crescent-shaped caldera, half of which is submerged, Santorini boasts the only sunken caldera in existence. This unique feature was formed by one of history’s most massive eruptions over 3,600 years ago, which obliterated the ancient city of Akrotiri and dealt a devastating blow to the Minoan civilization that once thrived here.

Today, Santorini – or Thira – stands as Greece’s top destination for romance. With luxurious villas and resorts offering opulent escapes for celebrities and picture-perfect settings for weddings and photoshoots, the island’s volcanic cliffs towering 1,000 feet above the Aegean create a breathtaking backdrop. It's no wonder it's one of the world's most photographed places.

As dusk falls, Santorini pauses for its iconic sunsets. The charming village of Oia, with its blue and white domes, fills with visitors eager to witness the golden hour. As the sun sinks behind the caldera, the sky bursts into a mesmerizing palette of reds, oranges, and pinks, leaving onlookers in awe as the last rays dip into the sea.

Beneath the vibrant, mesmerizing colors of Santorini lies an active volcano, often unnoticed.

Mysteries beneath the surface

Located within the Hellenic Volcanic Arc, one of Europe's most active volcanic zones, Santorini has witnessed more than 100 eruptions over the past 400,000 years. The region also includes Kolumbo, a highly active and potentially hazardous underwater volcano, just five miles northeast of Santorini.

Hidden beneath the Aegean Sea, Kolumbo has been dormant for nearly 400 years – but it's far from inactive. The last eruption in 1650 resulted in 70 casualties and a massive 40-foot tsunami. The event was accompanied by powerful earthquakes, aftershocks, toxic gases, and ash clouds.

Scientists are well aware of the potential devastation a Kolumbo eruption could cause. In recent years, numerous major oceanographic expeditions have studied it, and monitoring efforts have increased significantly. One of the largest US research vessels, the JOIDES Resolution, made its first Mediterranean journey to Santorini between December 2022 and February 2023.

The massive research vessel brought 'an entire floating laboratory' to the region, according to volcanologist and expedition co-leader Tim Druitt. Equipped to drill more than 8,000 meters (26,000 feet) below the sea’s surface, scientists collected valuable sediment samples to better understand the volcanic history of the area.

Initial findings, expected later this year, will not only aid in forecasting future eruptions but could also provide insights into the behavior of other dangerous volcanoes worldwide. This research will help predict potential threats to millions of people living near active volcanoes, while also exploring the connections between earthquakes and volcanic activity.

For the past 20 years, Evi Nomikou, a geological oceanographer from the University of Athens, has participated in every expedition on her home island of Santorini. 'We are slowly piecing together a geological puzzle, identifying which areas were once land and which were submerged,' she explains.

'By studying past eruptions and their effects, we can create a roadmap to better navigate future challenges,' says Nomikou.

An alien ocean

The JOIDES Resolution expedition is just the latest in a series of significant studies in the area. Nomikou recalls that the extreme conditions found at Kolumbo led NASA to fund a pioneering expedition in 2019. 'At the bottom of its crater lies an extraterrestrial ocean with life forms that could exist on other planets,' she explains.

The harsh environment, with active hydrothermal vents releasing hot water and minerals, provided a perfect testing ground for cutting-edge technologies, including Autonomous Underwater Vehicles. NASA used the mission to test submersibles that may one day explore alien oceans on moons of Jupiter and Saturn.

A recent study also uncovered a previously unknown magma chamber beneath Kolumbo. Scientists believe this discovery could be crucial in understanding the seismic activity in the region.

The dramatic volcanic landscape of Santorini inspired Hollywood filmmakers, who chose it as the backdrop for the opening scenes of the 2003 action film 'Lara Croft: Tomb Raider – The Cradle of Life.' With its towering cliffs, Angelina Jolie’s character faced perilous challenges in mysterious waters while searching for underwater treasure.

After filming wrapped, Angelina Jolie and her then-husband Brad Pitt vacationed on Santorini, and they weren’t alone. The island has hosted numerous other celebrities including the Kardashians, Lady Gaga, and Shakira. Each summer, luxury yachts ferry VIP guests between Santorini and Mykonos, another hotspot for the rich and famous, with their glamorous experiences shared in sparkling social media posts.

Crater treks and rejuvenating hot springs

While Brangelina’s love story may have ended, Lara Croft’s spirit of adventure continues to inspire boat tours on the island. One popular excursion takes visitors to the Nea Kameni volcano, part of the Santorini volcanic complex, which is also home to a national geological park.

'The last eruption of Nea Kameni occurred in the 1950s,' says Marios Fytros, CEO of Santorini View. 'Visitors are drawn to the excitement of hiking to the volcano’s crater. It’s one of our top tours.' Boat trips continue with a dip in the volcanic hot springs on the nearby Palea Kameni island, followed by drinks on deck with views of Santorini’s dramatic cliffs.

Another popular excursion takes visitors to the impressive archaeological site of Akrotiri, a powerful reminder of the volcano’s might. The prosperous Bronze Age city was obliterated by the eruption 3,600 years ago, which unleashed a massive 20-mile column of ash and rock, burying the city. A similar catastrophe would strike Pompeii some 1,700 years later.

Today, Akrotiri’s vibrant frescoes are remarkably well-preserved, now that the ashes and lava have been cleared away.

A seething volcano

Santorini’s worldwide popularity has driven some of the largest tourism investments in Greece. In recent years, high-end brands like Hilton and Nobu have opened their doors on the island, and property values are now among the highest in the country.

However, geologists – who are closely monitoring Kolumbo – caution that it’s only a matter of time before another major eruption occurs.

Yet in geological terms, 'time' moves incredibly slowly. One unnamed real estate agent on the island mentions that 'volcanic activity never comes up' when discussing property sales.

When Kolumbo does erupt, it has the potential to unleash a towering eruption column that could rise tens of miles high and trigger a tsunami. Although there were concerns about increased activity a decade ago, it has since subsided.

'If we begin to notice increased activity in Kolumbo, we’ll need to stay vigilant,' says Druitt. 'The good news is that volcanoes usually provide ample warning before erupting.'

In 2020, Greece’s Civil Protection Agency released a 185-page plan outlining how to address the potential consequences of an eruption within Santorini’s volcanic complex.

Volcanic cuisine and wine

For locals, the volcano is mostly a distant thought, relevant only during tours. During the summer, the island is overflowing with visitors. Overtourism remains one of Santorini's most pressing challenges, as its stunning landscape continues to draw massive crowds. Last year, the International Union of Geological Sciences, in partnership with UNESCO, added Santorini’s caldera to its inaugural list of the top 100 Geological World Heritage Sites.

Beyond hotels and restaurants, almost every business on the island is connected to the volcano. Locally crafted cosmetics harness the power of volcanic minerals, and premium food products are grown in the unique soil. There's even a museum dedicated to the Santorini cherry tomato, which has held Protected Designation of Origin status since 2006, and the island’s fava beans are considered the best in Greece.

Santorini’s most famous export, after tourism, is undoubtedly its wine. Locals joke that there’s more wine than water on the island.

About a fifth of Santorini’s nearly 30 square miles is covered by vineyards, with most cultivating assyrtiko, a native grape variety that produces crisp, dry, and – not surprisingly – mineral-rich white wines.

The iconic 'cave' houses, carved into the volcanic rock and known as yposkafa, are a favorite among honeymooners seeking their perfect getaway. But for Nomikou, who grew up on the island, it was Kolumbo – not the picturesque caldera – that shaped her childhood dreams.

'I was deeply shaped by the tales of my grandfather and great-grandfather. They recalled the smaller eruptions at Nea Kameni,' she says.

'But they always told me that the real threat is the one you can’t see.'

'Over time, I realized there was another volcano, hidden underwater. A more powerful, enigmatic, and dangerous one. We can't predict when the next major eruption will happen, but we know it’s inevitable.'

Santorini might one day be engulfed by ash again. But for now, as visitors savor another breathtaking sunset with a glass of assyrtiko, the volcano remains silent.