Descend into the Heart of an Icelandic Volcano

Accompany National Geographic Explorer Andrés Ruzo on an only-in-Iceland voyage deep inside the Earth.

Thrihnukagigur volcano near Reykjavík is an intact and dormant volcano, which last erupted 4,000 years ago.
Photograph by Parker Young

National Geographic Explorer Andrés Ruzo and Coors Light share a fervent desire to dream big and make those dreams come true. For Ruzo, the ultimate dream of his Icelandic expedition was being lowered into an intact volcano. In the third of four photo essays, join Ruzo as he achieves his goal and witnesses the geologic wonders preserved within a magnificent magma chamber.

Seeking Answers in The Volcano

Only about 30 minutes from Reykjavík, Iceland’s Thrihnukagigur volcano presents scientists and travelers with an experience you can’t find anywhere else: descending into heart of a volcano. Everything we’ve seen in Iceland has been so awesome, but the volcano is the reason we’re here.

A setting like this is unbelievably rare because the volcano did not collapse after its eruption. The magma retreated deep underground before cooling into hard rock and fully plugging the mouth, making the chamber stable enough withstand Iceland’s tectonic activity. The result is Thrihnukagigur’s spectacular chamber.

You cannot, however, talk about Thrihnukagigur’s uniqueness without the human element. Such places do not “protect themselves”—something I know intimately from working at Peru’s Boiling River. This is a conservation success story over four decades in the making. Here, geological uniqueness mixes with the best of the human spirit. As a result, the area is protected and sustainably managed, while still giving visitors authentic experiences and connecting them to nature in a meaningful way.

That is my holy grail for the Boiling River, and it is precisely why going into the volcano is at the top of my Icelandic to-do list. I want answers. I want to understand what the Icelanders did right—and to do that I need to go underground.

Reaching the Top

Lava fields covered in spongy yellow-green moss, and occasional patches of white snow, stretch as far as the eye can see. We start the roughly two-mile hike on the crushed rock trail to the Thrihnukagigur volcano. Everything about the landscape inspires a sense of isolation. It takes a cell phone going off to remind me that we are—incredibly—only a 30-minute drive from Reykjavík.

A stoic Icelandic colleague says the wind is blowing “normally,” which means “strong and frigid” for everyone else. Our excitement grows with every crevice we cross, crazy lava formation we see, or collapsed lava tube we spot. There is no question, though, that this excursion is safe, time-tested, and controlled. As someone who works on expeditions that are often quite the opposite, it is nice to not have to prepare for dangers and complex logistics. This is a chance to simply enjoy the hike—and it proves to be a blast.

We make it to the end of the trail as a helicopter banks above us, dramatically landing in front of the welcoming center at the foot of Thrihnukagigur. “That’s for those who can’t make the hike,” explains a local guide, ushering us through the doors to put on safety gear and receive a briefing. We meet the group that has just returned from the volcano—their awe-struck faces seem calm and composed in comparison to our frenetic excitement. Something special awaits us down there, and I cannot wait to see it.

Descending into the Volcano

We clip into the safety lines on the cage-like lift, which was custom-built to fit into the roughly 12- by 12-foot opening at Thrihnukagigur’s top. The lift system safely lowers you nearly 400 feet through the volcano’s throat and into a vast, open, and spectacularly lit chamber that goes down to 700 feet, and could easily fit the Statue of Liberty in it. Our guide gives the final security check to our helmets, safety harnesses, and gear bags. It is time.

We descend into the black. “There are two speeds,” says our guide in a thick Icelandic accent, “slow and slower. Here, it is safety-first. The lift makes a 400-foot drop in about seven minutes. Rappelling down takes longer.”

I watch a geologic story pass before me, painted into the rust reds and matte-blacks of the walls. Beautiful textures tell of molten rock shooting towards the surface and dripping back down again to freeze into endless rows of sharp, cone-shaped spikes.

The lift shutters and slightly tilts—wheels on the lift’s side roll us down a particularly tight squeeze, only to leave us hanging again in the void. We are out of the neck and Thrihnukagigur’s vast main chamber opens before us, so tastefully and beautifully lit that it feels like descending into a cathedral. There is something sacred about it.

Exploring the Chamber

Being inside Thrihnukagigur makes me feel like a cardiac surgeon who has been miniaturized to explore the chambers of human heart. It is spectacular. A single bright beam of bluish light shoots down from the world above, highlighting what appeared as a living chandelier of dripping water droplets in a part of the chamber. Though the magma is long gone and unlikely to ever return, something about this place feels alive.

As far as volcanoes go, Thrihnukagigur is tiny—it is only about 130 feet above the surrounding plain (some volcanoes rise thousands of feet over their landscapes). But it is precisely this small size that helps protect the chamber from 4,000 years of tectonic activity.

The very concept of how to properly define a “magma chamber” is a hot topic in geology. The single-chamber model is inadequate, and studying a feature buried in miles of solid rock is not easy. Presently, the concept of a “magmatic system” is volcanology’s best way to describe what we are looking at, as it encompasses the vast, complex network of chambers, columns, and tunnels that originate miles deep in the Earth’s interior.

There are many places on earth where we can study such systems, but you are mostly limited to exploring eroded, extinct volcanoes exposed at the surface. Thrihnukagigur makes the otherwise inaccessible accessible—not just because it is geologically young and well-preserved, but because the human installations allow you to experience it in its full glory.


From the moment our visit started, I knew I did not want it to end. The attraction stands as a monument to our planet’s molten lifeblood, as well as over 40 years of human effort to turn this place into one of Iceland’s top visitor destinations.

I descended with questions about how to best preserve sensitive geologic sites, while giving visitors access to an authentic connection. Stepping onto the lift-for the ride up, I have my answers.

Walking down the volcano, we pass a frenetically excited group eager for their trip down. This time it is our group giving off the calm, composed, even vulnerable energy from having experienced awe.

The tour guides must be aware of the vulnerability with which awe leaves you, because, back at the center, we are greeted with comfortingly warm bowls of Icelandic soup. I saw a quote from The Guardian describing the excursion as, “a strangely emotional experience.” I could not agree more.

At Thrihnukagigur, the Icelanders did it right. The two-mile hike in makes me feel like I earned my time in the volcano. Controlling the number of people in the chamber gives visitors the gift of silence and space. It is controlled accessibility that protects this place from becoming a cattle-call tourist attraction.

It really is a moving experience, but people conserving natural sites need to give visitors the space to be moved. The Icelanders have made this place accessible, but in a way, that respects the volcano by keeping the right amount of inaccessibility. We can’t force anyone to experience awe, just as we can’t force a plant to grow, but given the right environment, magic happens. We just need silence, space, and time.

I think that to be human means to push boundaries, like I did on this journey into the volcano. As a National Geographic Explorer, it’s easy to think that I’m already out there, doing it all and seeing it all. But from that simple question that Coors Light posed to me, “What’s Next?” stemmed a realization inside me that there’s always more to see, more to explore, and more to learn.