Descent
120 m
An open-cage elevator descends 120 meters through the volcanic vent into the magma chamber
Þríhnúkagígur: Inside a Volcano's Magma Chamber
The only place on Earth where you can descend into a volcano's magma chamber
Location
Reykjanes Peninsula
Bláfjöll area, near Reykjavík
Quick Answer
Þríhnúkagígur is a dormant volcano near Reykjavík where an elevator lowers visitors 120 m into the magma chamber. Last eruption 4,000 years ago; tours May to.
Þríhnúkagígur (meaning "Three Peaks Crater") is the only place on Earth where you can descend into the magma chamber of a dormant volcano. Located on the Reykjanes Peninsula in the Bláfjöll mountain area, just 30 minutes from Reykjavík, this volcano last erupted approximately 4,000 years ago. When the eruption ceased, the magma drained away completely rather than solidifying inside the chamber, leaving an empty cavity roughly the size of the Statue of Liberty. The chamber walls are streaked with reds, oranges, yellows, purples, and greens from different mineral deposits. Visitors descend 120 meters via an open-cage elevator through the narrow volcanic vent into this vast underground space, guided by the "Inside the Volcano" tour operation.
Sources and page update
Updated: 2026-09-10
Access is by guided tour only. Helmets and harnesses are provided. Moderate fitness required for the 45-minute hike to the crater. Not recommended for those with claustrophobia or fear of heights.
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Official sources to check
Season
May - Oct
Tours operate during the summer season, typically from mid-May through late October
Access
Guided only
Only accessible through organized guided tours operated by Inside the Volcano
What to Expect
Elevator Descent
An open-cage elevator lowers visitors 120 meters through the narrow volcanic vent, taking about 7 minutes with views of the rock walls changing color as you descend.
Vast Magma Chamber
The chamber is enormous, large enough to fit the Statue of Liberty. The floor area spans roughly 3,500 square meters of volcanic rock.
Mineral Color Walls
The chamber walls display vivid bands of red, orange, purple, yellow, and green created by iron, sulfur, copper, and other mineral deposits.
Guided Exploration
Guides explain the geology and history of the volcano during the 30 minutes spent inside the chamber.
Scenic Hike In
The tour begins with a 45-minute hike across a moss-covered lava field to the crater opening, with views of the surrounding Bláfjöll mountains.
Base Camp Refreshments
A heated base camp near the crater provides warm soup and drinks before or after the descent, a welcome comfort in the highland weather.
Getting There
Meet the operator at its mountain ski cabin, reached by your own car or a separately booked Reykjavík pickup. From there, the guide leads the walk across the lava field to base camp. Do not start walking independently. The tour page lists 3 km each way and about 45–50 minutes for the approach; allow about four hours at the site, or five to six hours including Reykjavík transfers.
Best Time to Visit
The operator lists May 5–October 30 as its season. Choose an available departure and check the forecast for the outdoor hike, even if Reykjavík feels warm. Wear hiking shoes and warm, rainproof clothing. The chamber is around 4°C, and the return walk is part of the tour. Confirm any weather-related changes with the operator.
Can children do the approach?
The minimum age is eight. The uneven lava-field walk still matters after that birthday: children need to manage both directions in wind or rain. The operator’s family guidance asks parents to plan for up to 3.5 km each way. Discuss concerns before booking; it says a child’s inability to finish the walk does not qualify for a refund.
Planning help
Þríhnúkagígur FAQs
Quick answers with safety notes where it matters.
How do you get inside Þríhnúkagígur volcano?
Visitors descend into the magma chamber via an open-cage elevator (similar to a window-washing platform) that lowers you approximately 120 meters through the volcanic vent. The experience is operated by Inside the Volcano and is the only way to access the chamber. The descent takes about 7 minutes and a guide accompanies you throughout.
Is the Inside the Volcano tour safe?
Yes, the tour is operated with strict safety protocols. All visitors are provided with helmets and harnesses. The elevator is regularly inspected and maintained. The volcano has been dormant for over 4,000 years and shows no signs of renewed activity. Group sizes are kept small, and experienced guides lead every tour.
How much does the Inside the Volcano tour cost?
The operator lists 51,000 ISK for adults and 25,000 ISK for children aged 8–12, checked September 10, 2026. Reykjavík pickup costs extra. Check your selected departure and transport option before paying.
Why is Þríhnúkagígur unique among volcanoes?
Þríhnúkagígur is the only known volcano on Earth where you can enter the magma chamber. In virtually all other volcanoes, the magma chamber collapses or fills with solidified rock after the final eruption. At Þríhnúkagígur, the magma drained away completely and left behind a vast, intact chamber with walls colored by different mineral deposits.
For a countrywide view of Iceland’s volcanic systems, explore our Iceland statistics.