Veins Of The Earth: Crawling Inside An Active Volcano

Piton de La Fournaise Reunion
Volcano Piton de La Fournaise
Reunion Island, France

Sweat drenched my shirt as I stumbled through pitch black darkness, groping at jagged glass-like walls for support while trying not to hit my head on the shrinking ceiling.

We were deep inside Piton de la Fournaise, an active shield volcano on Reunion Island. It’s part of Réunion National Park, a UNESCO Heritage Site.

Earlier our group explored the desolate red landscape on top of the volcano at La Plaine des Sables, which looks very similar to NASA pictures I’ve seen of Mars. Bizarre rock formations in many hues of red laid out across rolling hills and craters in all directions.

The sudden change of scenery from lush green forests to red apocalyptic wasteland is quite shocking.

La Plaine des Sables Reunion Island
La Plaine des Sables Volcanic Highway
Volcano Reunion Island
Red Martian Landscape

Piton De La Fournaise

Reunion is a tiny French island off the East coast of Africa. The tip of a giant underwater volcano that rises 4000 meters from the bottom of the Indian Ocean. It’s one of the most active volcanic hot-spots in the world with over 150 recorded eruptions since the 17th century.

In fact the “peak of the furnace” erupted just a few days before we arrived.

However these particular lava tubes we were exploring are left over from an eruption in 2010. The lava cooled off and stopped flowing through them years ago, we weren’t in any danger.

The June 2014 eruption occurred on a different side of the volcano.

Volcano Reunion Island
Entrance Into the Underworld

Inside The Earth

Kneepads and helmets are strapped on before following our Laventure guides over a hardened black lava field dotted with green plants. Volcanic soil is incredibly fertile due to the large amounts of iron, magnesium, potassium, and other minerals that it contains.

The entrance to the caves is through a small hole in the crust.

It looks a bit like a gaping mouth. We switch our headlamps on and climb down into the darkness.

Lava tubes are formed when ribbons of red hot lava drain from a volcano, the edges cool down and thicken into an insulating crust, creating a roof over the still-flowing lava.

Eventually the flow gets diverted or stops altogether, leaving tunnels.

Volcano Reunion Island
Exploring Volcanic Lava Tubes

Exploring Lava Tubes

Lava tube walls are very shiny, almost glass-like, reflecting the light of our headlamps. Frozen stalactites of lava drip from the ceiling to create “lavacicles” of different shapes and sizes.

The passageway is 8-10 feet wide, and 5-6 feet tall for much of the hour-long hike. However some sections are much smaller — making it necessary to crawl on your hands and knees.

Portions of the ceiling frequently erode and fall in, hence the importance of wearing a helmet while exploring these veins of the Earth. Brightly colored mineral deposits of iron & sulfur line the crumbled basalt in hues of red, orange, and yellow.

Occasionally you’ll find small holes leading up to the surface, the death-mask of a tree burned away by the lava leaving behind a hollow tube.

Volcano Reunion Island
Tight Squeeze

Reunion Volcano Adventure

At one point we all turn off our headlamps and hold on to each other, attempting to move forward in total darkness. It’s clumsy and difficult, a few of us hit our heads on the ceiling.

It’s amazing to think about the ribbons of hot lava that flowed through these tubes only a few years ago. Volcanoes are much more than death & destruction, they also bring rebirth.

Coughing up minerals from the center of the Earth and creating new land mass on which plants & animals will eventually thrive.

Hiking deep through the volcanic lava tubes inside Piton de la Fournaise on Reunion Island was a fun learning experience. I have a deeper appreciation for what Mother Nature is capable of. ★

Travel Planning Resources For Reunion Island
Location: Reunion Island, France
Accommodation: Cases Couleurs
Company: Tours Reunion

Packing Guide

Check out my travel gear guide to help you start packing for your trip. Pick up a travel backpack, camera gear, and other useful travel accessories.

Book Your Flight

Find cheap flights on Skyscanner. This is my favorite search engine to find deals on airlines. Also make sure to read how I find the cheapest flights.

Rent A Car

Discover Cars is a great site for comparing car prices to find the best deal. They search both local & international rental companies.

Book Accommodation is my favorite hotel search engine. Or rent apartments from locals on Airbnb. Read more about how I book cheap hotels online.

Protect Your Trip

Don’t forget travel insurance! I’m a big fan of World Nomads for short-term trips. Protect yourself from possible injury & theft abroad. Read more about why you should always carry travel insurance.

Enjoy This Post? Pin It!

Bucket List: Crawling Inside An Active Volcano! More at
Bucket List: Crawling Inside An Active Volcano! More at


I hope you enjoyed my guide to crawling inside an active volcano! Hopefully you found it useful. Here are a few more wanderlust-inducing articles that I recommend you read next:

Are you as fascinated with volcanoes as I am? Ever seen one before? Share with us in the comments below!

#GoToReunion is made possible in partnership with iAmbassador and Reunion Island Tourism. As always, the content & opinions expressed here are entirely my own.


Hi, I’m Matthew Karsten — I’ve been traveling around the world for the last 10 years as a blogger, photographer, and digital nomad. Adventure travel & photography are my passions. Let me inspire you to travel with crazy stories, beautiful photos, and money-saving travel tips.
Matthew Karsten
Join 20,000 others who receive exclusive email updates!

7 Reasons To Subscribe →
As an Amazon Associate I earn from qualifying purchases. I'm also a member of other affiliate programs. For more info please read my policy page.

Leave a Comment

Comments (8)

  1. You had me worried then, I live in France and was thinking I didn’t know there was a live volcano and it would be just my luck if I lived right next to it. Glad to see it was actually nearer Africa, looks like a great adventure though, if you are only visiting!

  2. Very cool! One thing that truly stands out about volcanoes is the amount of amazing color both inside and out. Any moments of claustrophobia in there?

    • Loved the colors hidden under the black basalt in the tubes. No claustrophobia for me, I love caves. But my friend Keith had a small panic attack near the end of the hike. Luckily we were near an exit! He just needed some fresh air.