Descending into Þríhnúkagígur’s Magma Chamber

Ride an open lift 120 metres into the only intact magma chamber visitors can enter, its walls glowing purple, red and ochre.

Six Minutes Down

Þríhnúkagígur is the only place on earth where you can go down into an intact magma chamber. From the meeting point, a three-kilometre walk of about 45 minutes crosses the lava field to a base camp. The lift is an open cable elevator, first built in 2010 for scientists, hanging from a steel bridge over the crater. It takes six minutes to drop 120 metres.

At the bottom you have around 35 to 40 minutes in a chamber whose floor covers more than 3,000 square metres, among rock formations and frozen magma, with walls that run through deep purple, red, orange, yellow and ochre. It stays at about 6°C whatever the season.

Why the Chamber Is Empty

Iceland straddles the Mid-Atlantic Ridge, where the North American and Eurasian plates meet, and has more than 130 volcanoes, dormant or active. The lava fields around Þríhnúkagígur were laid down by eruptions over the past 50,000 years.

Normally, magma gathers in a chamber underground, builds pressure and forces its way up, and what’s left solidifies inside once the eruption ends. Here, scientists think the magma sank back down into the crust instead, leaving the chamber hollow and whole. The colours come from minerals left by cooling magma, from sulphur-rich gases released in the eruption, and from microbes that have colonized the rock over thousands of years. Icelandic cave explorer Árni B. Stefánsson discovered it in 1974; only experienced climbers could reach it until the lift arrived in 2010, and it opened to the public in 2012.

The Chamber to Yourselves

The standard tour takes groups of up to 18, with several departures a day in peak season. The lift carries only a few at a time, so you go down and up in batches, and your time at the bottom moves at the group’s pace.

There are two private options: a dedicated 7:30 am departure, or buying out an entire 18-seat departure. Either way, the chamber is yours with no other visitors. Your guide’s attention is undivided, so the story of what the chamber is, how it formed and what the colours mean can go as deep as you like, and its extraordinary silence is far more powerful when you aren’t sharing it with a crowd. It’s an unforgettable morning for a couple, friends or a family. If the three-kilometre walk isn’t possible, you can arrive by helicopter.

Across the Lava and Into the Earth

The walk crosses moss-covered rock, ancient lava and volcanic fissures, and the crater comes into view about a kilometre away. At the rim the steel bridge spans the opening, with the lift platform above the drop. The first seconds of the descent reveal the scale below; by the time you touch down, the opening overhead is a small circle of light 120 metres up.

The floor is uneven and needs careful footing in places. The walls run from deep purple high up, where sulphur deposits concentrate, through red, orange and yellow as you go deeper, to ochre and brown at the base, where the rock is oldest. The ride back up takes the same six minutes, and soup and hot drinks are waiting at base camp. Your Out Of Office LGBTQ+ travel specialist can build the day around a welcoming hotel in Reykjavik.