Marc Caillet is among a group of volcano-savvy amateurs from Geneva's Volcanologic Society, who's been on multiple trips to one of the world's largest volcanoes, which is situated in one of the world's most volatile countries.
Deep in the Democratic Republic of Congo, the Nyiragongo is a picturesque 3,470m high volcano, the most active in the region.
You're in a heavy suit, one tiny metre away from a 240m wide boiling lava cauldron. It was a dream.
The cone shaped mountain didn't get famous for spectacular explosions like other stratovolcanoes like Mt St Helens, or Vesuvius but it is still deadly, causing casualties in 1977 and destroying a good part of the city of Goma in 2002. The lava lake – which sits 400m deep inside the crater – is the biggest in the world.
In doing so, Caillet became the first man to ever reach the edges of the biggest lava lake in the world, 400m deep inside the crater of one of Africa's most notable volcanoes, the Nyiragongo.
The group of scientists and amateurs went on four expeditions between 2003 and 2009 before finally reaching the edges of the lava lake, in 2010, accompanied by photographer Olivier Grundewald.
“It had been our goal for a while to reach the bottom of the crater,” says Caillet.
We had been trying to get down there for years, as close to the lava lake as possible, so when I finally got to the bottom it was an amazing sensation, absolutely extraordinary.
You're in a heavy suit, one tiny metre away from a 240m wide boiling lava cauldron. It was a dream becoming reality and it was absolutely fantastic.”
But getting there wasn't simple: the top of the 1,000m wide crater is at an altitude of over 3,000m. Once up the steep mountain side, the heavily packed team has to go back down inside the crater, for 300m of mostly vertical descent to the camp, then another 100m down to the very bottom.
We were a bit scared... if the wall broke, the part where we were standing would quickly fill up with lava, and we had no easy way out.
“Since the lava lake is smaller than the crater, there is a cone-like shape in the middle, containing the lava,” adds Caillet.
We had to climb up on all fours up the lake's wall with our heavy suits, to get to the edge of boiling magma to finally reach our goal and see this mesmerizing view.
“The edges of this cone were about 10-12m above us when we were at the very bottom so we couldn't see except for smoke going up. We were a bit scared at this point: if the wall broke, the part where we were standing would quickly fill up with lava, and we had no easy way out!”
“The whole scene was amazingly picturesque. When you're at the bottom, there's an incredible atmosphere. We spent many hours there and at night, all the walls are lit by the red glow of lava.
Sometimes we're able to see the immensity of the African sky through the smoke coming up the lake. You don't need a headlamp: the whole place is lit up!
We do the climb up at night to come back to our base camp and it's just red everywhere... it's surreal... and absolutely extraordinary. Talking about this just makes me want to go back a seventh time!”
Will they return? Well, that all depends on the local political situation – which has the park closed to visitors. But as soon as it re-opens, you can be sure to see Caillet and his friends from the Geneva Volcanologic Society will venture up the flanks of the Nyiragongo once again.
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