Would you run a marathon 1,120m underground? Because the world’s deepest marathon is taking place in October 2025 in Sweden, with 60 intrepid runners taking on the challenge.
This is a run on another level!
The world’s deepest marathon will take place inside Boliden’s Garpenberg zinc mine on 25 October 2025.
The run is 1,120m or 3,675ft underground.
60 runners from around the world will run the world’s deepest marathon.
3D route mapping was used to create the route for the run.
Runners will face temperatures of 30ºC in total silence and will be running in total darkness, wearing head torches for light.
Runners will be equipped with helmets and personal protective equipment, and will have access to rescue chambers as part of strict safety measures to protect runners in this unique environment.
The run aims to raise $1m USD for charity.
THE WORLD’S DEEPEST MARATHON WILL BE A TRUE TEST FOR RUNNERS
No marathon has ever been run this far underground and it’s an extreme environment and an extreme test of physical and mental endurance.
Organized by high-tech metals company Boliden, personal development group BecomingX, and the International Council on Mining and Metals (ICMM), it’s been described as a “true test,” by Bear Grylls, co-founder of BecomingX.
“Running a marathon is tough, but doing it 1,120 metres below sea level, in total silence and darkness, will push participants to their limits,” said Grylls.
“It’s a celebration of human resilience and a statement on the transformation of the mining industry,” is how mining.com have described the marathon, with the run showcasing how mines are no longer like the dangerous tunnels of the past.
HOW DEEP IS THE WORLD’S DEEPEST MARATHON?
At 1,120m below sea level, it’s very deep. That’s four-times the height of the Eiffel Tower, underground. Here’s how it compares to other monuments.
WILL IT BE EASIER TO RUN UNDERGROUND?
At lower altitudes, there will be higher air pressure which theoretically means more oxygen – potentially 10-times more than at sea level – which could improve endurance performance.
However, there is more air density at that altitude, meaning more air resistance which could slow runners down.
But with high temperatures and high humidity, plus the challenging dark conditions (and we have no idea what the underfoot conditions will be like!), this will definitely not be an easy run and it’s not going to be a run for those chasing a new personal best!
WHAT’S THE WORLD’S HIGHEST MARATHON?
According to Guinness World Records, the highest marathon ever run was the World’s Highest Marathon on Mount Kilimanjaro, Tanzania on 9 May 2022. It took place at a maximum altitude of 5,895m. The run included 1,800m of elevation gain.
There’s also the Everest Marathon which takes place from Everest Base Camp at 5,356m. The race is mostly downhill for the hundreds of runners who take place each year.
TL;DR ON THE WORLD’S DEEPEST MARATHON
The world’s deepest marathon takes place 1,120m underground inside Boliden’s Garpenberg zinc mine in Sweden on 25 October 2025. Over 60 people will run in 30ºC temperatures in darkness and silence, wearing helmets for safety and a headtorch to light the way.
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Lead image from Boliden Garpenberg