The marathon was held inside Boliden’s Garpenberg mine in central Sweden. The event broke two Guinness World Records and spotlighted not only human resilience, but also the sophistication and safety of modern underground mining.
 
Organised by Boliden, in partnership with the International Council on Mining and Metals (ICMM) and BecomingX, the marathon took place 1,120 metres below sea level in one of the world’s oldest and most advanced mining operations. Runners completed 11 laps of a 3.84 km course through Garpenberg’s dimly lit tunnels, covering the full 42.195 km marathon distance in conditions few athletes will ever experience. Temperatures hovered around 30°C, humidity was high, and oxygen levels lower than at surface level - a stark contrast to conventional marathon environments.

“It was a privilege to host the world’s deepest marathon in a working mine that epitomises modern, safe and responsible mining,” said Mikael Staffas, President and CEO of Boliden. “This event shows what is possible when innovation, safety, and human spirit come together underground.”

A first for mining and a first for marathon history

The event made history as the first full marathon ever run over a kilometre underground, officially setting world records for both the deepest marathon and the deepest organised sporting event. While the course was carefully monitored and lit for the runners’ safety, conditions remained uniquely challenging - narrow passageways, steep gradients, and constant darkness made each lap a mental as well as physical trial. Among the 60 participants were professional runners, mining professionals, and adventurers from across the globe.

Mining meets human endurance

The underground marathon was not only a sporting milestone, but also a platform for storytelling and philanthropy. The initiative aimed to raise over US$1 million for global charitable causes, while simultaneously showcasing mining’s role in innovation, safety, and community engagement.
Boliden’s Garpenberg mine was an ideal host. One of the oldest mines in Sweden — in continuous operation since the 1200s - it now ranks among the world’s most technologically advanced and safest underground operations. Its modern ventilation, monitoring, and communication systems made it possible to host a large-scale event without interrupting regular mining production.

Beyond the finish line

The event also served as a bold public relations moment for the mining industry, often perceived as traditional or opaque. By inviting global participants, livestreaming parts of the race underground, and linking the challenge to broader themes of resilience and purpose, Boliden and its partners turned a working mine into a stage for global collaboration.

As the runners emerged from the deep tunnel, each step marked more than personal achievement. It marked a statement: that mining today can host one of the toughest athletic challenges in the most demanding of environments - and still maintain high standards of safety, supervision and community focus. For industry observers, it offers a unique narrative: rare, dramatic, and symbolic of how mining continues to evolve.

Some of the companies represented:

•    Gold Fields
•    Kumba Iron Ore
•    Glencore
•    AngloGold Ashanti
•    Hindustan Zinc

Participants included mining professionals, engineers, and corporate representatives. The event was sponsored by Teck, World Gold Council and Hindustan Zinc.