In Iceland, tours head inside a giant tunnel cave carved out after a volcanic explosion.
Darkness inside Vidgelmir
“If you can see your hands in front of you, then I have bad news,” says the guide. “You are crazy.” We’re about 500 metres inside Vidgelmir, a long tunnel-like cave dug into the barren landscape of western Iceland. The lights have been turned out, and it is pitch black. You’d not want to hide away in here without a good torch and a plentiful supply of batteries.
And, for that matter, a big coat. The wind howling in from outside keeps the temperature at about freezing point. At one point, however, it would have been considerably warmer down here.
Vidgelmir was formed by lava. Around 1,100 years ago it poured down from a volcano now covered by the Langjökull glacier.
Why book a Cave Explorer tour in Iceland?
- 🕳️ Discover Iceland’s hidden underground world inside a lava tunnel
- 🧑🏫 Learn how volcanic activity shaped the landscape from expert guides
- 🔦 All gear provided, including helmet and headlamp
- 🚐 Small-group tour with transfers from Borgarnes or Reykholt available
- 📷 Great chance to take surreal photos inside natural lava formations
The creation of Iceland’s giant lava cave
The initial flow was smooth, relatively slow and relatively slow to cool – which in volcanologists’ terminology made it “pahoehoe” lava. And pahoehoe lava has a tendency to create tubes around it as gravity takes its course and makes it flow down hillsides.
The mile-long cave we’re in was essentially the lava stream, and parts of it are weirdly smooth. The walls look more like the mildly rippled chocolate coating on a Mars bar than rock. A less charitable interpretation would be that it’s the result of, erm, a loose stomach. The brown, gloopy look is not entirely appealing, but it’s a result of the lower melting point – it remains as a liquid longer than the faster flowing, thicker lava.
It is mixed up with the occasional streaks of red, green and yellow from iron, chloride and sulphur present during the eruption.
The chocolate coating inside Vidgelmir
But the bigger puzzle is the massive chunks of rock all over the cave floor. These all seem to have a similar chocolate coating – but only on one side.
The answer is that, at some point, they have fallen off the walls and ceiling, leaving the more conventional basalt rockface uncovered. And once this dawns, a few fairly obvious worries about being crushed by humungous breakaway boulders kick in.
Is Iceland’s lava cave dangerous?
The dangerous period, however, is over. Most of the tumult would have occurred in the first few years after the cave was formed. The rocks are still technically cooling after hundreds of years, but for a couple of decades following the eruption, they would have been properly hot. During the cooling process, they would have solidified and shrunk slightly, leading to cracks. Those cracks would destabilise the chunks that broke off. Now, however, enough time has passed for everything to remain fairly safe and solid.
But that’s not to say it couldn’t happen all over again, though. On our way back into the open air, and the bleak, moss-covered landscape, the guide lets us know that the volcano is still active. “So if you start to feel very warm all of a sudden, let me know.”
Booking the lava cave tour
Tours of Vidgelmir are available through The Cave. Advance bookings online are recommended.
Entrance fees for Vidgelmir lava cave
Access to the Vidgelmir lava cave is strictly limited to guided tours, ensuring the preservation of its delicate formations. The general admission price covers the guided “Cave Explorer” tour, which includes the necessary safety equipment.
| Ticket type | Price (ISK) | Notes |
|---|---|---|
| Adult (Ages 16+) | From 8,500 ISK | Includes the 90-minute “Cave Explorer” guided tour, helmet, and headlight. |
| Youth (Ages 7–15) | 4,000 ISK | A reduced rate is available for children within this age bracket. |
| Children (Ages 6 and under) | Free | Young children enter free of charge but must be accompanied by an adult. |
| Self-guided access | Not permitted | Entry to the cave is only allowed with a registered guide from the landowner. |
Nearby attractions to Vidgelmir cave
Vidgelmir is located within the Hallmundarhraun lava field in West Iceland and is a prominent feature of the popular Silver Circle driving route.
- Hraunfossar and Barnafossar waterfalls: These two waterfalls are located a short drive away. Hraunfossar is notable for its numerous trickles streaming out of the edge of the lava field, while Barnafoss is a turbulent, narrow cascade.
- Deildartunguhver hot spring: Europe’s most powerful hot spring is nearby, pumping vast amounts of boiling water which is then used for heating in nearby towns.
- Húsafell and Krauma spa: Húsafell is a small settlement and recreational area, often used as a base for exploring the region. Krauma is a geothermal bath complex that draws water directly from Deildartunguhver.
- Langjökull glacier: Iceland’s second-largest glacier is accessible for tours, including snowmobiling and explorations of man-made ice caves.
FAQ: Visitor questions about Vidgelmir
Guidance for preparing for a trip into one of the world’s largest lava tubes.
| Question | Answer |
|---|---|
| How long does the tour inside Vidgelmir take? | The standard “Cave Explorer” tour lasts approximately one and a half hours (90 minutes). |
| Is the lava cave accessible for all ages? | Yes, Vidgelmir is noted for its high accessibility. It features paved paths and sturdy metal walkways with lights throughout the 1.5 km tube, making it suitable for most visitors, including young children. |
| What should I wear for the cave tour? | The temperature inside the cave remains low, regardless of the outside weather. Visitors must wear warm layers, a hat, gloves, and sturdy, waterproof footwear with good grip. |
| Can I take photos inside the cave? | Yes, photography is permitted. However, visitors must not touch or break off any of the rare and irreplaceable lava formations, stalagmites, or stalactites. |
More Iceland travel
Other great Iceland travel experiences include Northern Lights tours, Reykjavik food walks and whale-watching cruises.
Other Iceland travel articles on Planet Whitley include:
- Should you tackle Jökulsárlón as a day trip from Reykjavik?
- Seeing Jökulsárlón’s icebergs up close on a RIB cruise.
- A review of the Inside the Glacier tour.
- How many bottles of wine can you bring into Iceland?
- Snorkelling between two continents in the Silfra Fissure.
