Imagine being able to walk inside a glacier, stand in absolute darkness in a tunnel forged by boiling lava thousands of years ago, or snorkel through a fissure in the tectonic plates separating two continents.

Imagine doing all this within just a few days, without feeling rushed. Plus, of course, doing it safely, with professional guides who’ve come from all over the world to work in a country where such adventures are even possible, and for a company that strives to make them accessible to just about everyone.

The country is Iceland, as you might have guessed, and the company is Arctic Adventures. I spent five days in early May experiencing some of its most popular adventures, including the above.

Here’s the first of my three standout favourites — Katla Ice Cave Tour by Super Jeep.

Remember the volcano in Iceland that erupted in 2010 and caused chaos across Europe, with flights grounded for five days because of wind-blown ash?

That was Eyjafjallajokull. Its “big brother”, Katla, is far more feared and, historically, more destructive. Like Eyjafjallajokull, Katla is buried deep under a glacier, with 200m-700m of ice sitting on top, creating enormous downward pressure.

When Katla erupts again — and it’s overdue by a few decades — boiling magma will explode as it rises and reaches the ice cap, producing clouds of ash, splinters of jagged ice, and raging rivers of muddy water.

“And this just turns into an ocean with icebergs as big as apartment buildings that will come rolling down,” says our guide, Steinthor Birgisson, as we stand on Katla’s enormous flood plain and try to imagine what that’s like.

After the last big eruption, in 1918, all that was left after floodwaters drained and icebergs melted was black pumice and sand. This is the darkest, most dramatic landscape I’ve ever been in, and the appeal to film the opening scenes of the 2016 movie Rogue One: A Star Wars Story here is obvious.

After leaving the seaside village of Vik, we drive inland until the road ends, then transfer to what’s called a Super Jeep. It has big tyres with easily adjustable pressure and suspension to handle various terrain, including this plain of pumice.

In 15 minutes or so, we reach the edge of the Kotlujokull glacier, one of 11 tongues of ice flowing off the massive Myrdalsjokull ice cap, which covers Katla. Like most glaciers in the world, this one is shrinking because of global warming.

We pull crampons over our boots, don helmets, and followed Birgisson up what looks like a black-and-white mountain. But our eyes are lying. “There is no mountain here. It’s all ice”, he clarifies. Ice, covered in volcanic ash.

“And I know it can be a little hard to get your head around it, but that’s the way it is,” Birgisson adds.

After a gentle uphill walk, we reach our objective — a yawning, tunnel-shaped hole in the glacier created by meltwater. Icicles drip from the entryway, but the cave is big enough that none of us need to crouch. In places, wooden planks have been laid so we can walk without getting our boots wet.

Inside, the ice changes colour from black and white, to blueish green. We take our time, touching the ancient walls and ceiling, noting tiny bubbles in the ice — pockets of air that were trapped in snow, which was gradually compressed into ice by the weight of more snow on top.

The cave is as beautiful as it is ephemeral. Birgisson says it’s a little different every time he visits, with meltwater continually changing its appearance, but unlike other natural ice caves in Iceland, which are too unstable to visit from spring through fall, this one can be safely explored year-round.

For now, at least.

Birgisson tells us he’s been waiting his whole life for Katla to explode. “Through the last millennia, it’s been really active and really regular,” he says, almost wistfully. “Like, once a century.”

Katla may appear dormant under its blanket of ice, but it’s still one of Iceland’s most seismically active volcanoes. Birgisson’s tours have been cancelled at least three times in the five years, “because there was something cooking up there, you know, something was shaking and smelling”.

No one wants to be anywhere near here when Katla’s fury is next unleashed, but to be able to visit now, while Katla is sleeping, truly feels like a “now or never” experience.

+ Suzanne Morphet was a guest of Arctic Adventures. They have not influenced this story, or read it before publication.

fact file

Arctic Adventures, founded in 1983, is Iceland’s largest adventure tour operator, specialising in small-group tours led by expert guides. The company focuses on quality, safety and sustainability.

Katla Ice Cave Tour by Super Jeep can be booked as a day tour from Reykjavik, Iceland’s capital, or the village of Vik. From $US195 ($275) per adult. It can also be part of a multi-day adventure tour.

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