James Mason Wins World’s Deepest Underground Marathon in Swedish Mine
James Mason, a runner from the UK, won the world’s deepest marathon held 1,120 meters below sea level in the Garpenberg zinc mine in Sweden. The event, which took place in October 2025, attracted 55 participants from 18 countries, all of whom became Guinness World Record holders upon completion. Mason, who had not competed in a major race for over a decade, was motivated by the unique challenge despite the daunting conditions. Runners faced stifling heat of 24C, 72% humidity, and utter darkness illuminated only by headlamps. Safety regulations prohibited headphones, forcing participants to run in silence amidst the monotony of grey rock walls and the hum of mining machinery. The course required runners to traverse a five-meter-wide tunnel back and forth 11 times to complete the full marathon distance. Mason prepared by training in the dark and wearing safety gear during summer runs. He described the experience as unnerving due to the 1,300 meters of solid rock overhead but ultimately rewarding. The article highlights his personal journey from casual family running to achieving this extreme athletic feat, emphasizing the psychological and physical challenges of underground endurance sports.
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James Mason Wins World’s Deepest Underground Marathon in Swedish Mine
James Mason, a runner from the UK, won the world’s deepest marathon held 1,120 meters below sea level in the Garpenberg zinc mine in Sweden. The event, which took place in October 2025, attracted 55 participants from 18 countries, all of whom became Guinness World Record holders upon completion. Mason, who had not competed in a major race for over a decade, was motivated by the unique challenge despite the daunting conditions. Runners faced stifling heat of 24C, 72% humidity, and utter darkness illuminated only by headlamps. Safety regulations prohibited headphones, forcing participants to run in silence amidst the monotony of grey rock walls and the hum of mining machinery. The course required runners to traverse a five-meter-wide tunnel back and forth 11 times to complete the full marathon distance. Mason prepared by training in the dark and wearing safety gear during summer runs. He described the experience as unnerving due to the 1,300 meters of solid rock overhead but ultimately rewarding. The article highlights his personal journey from casual family running to achieving this extreme athletic feat, emphasizing the psychological and physical challenges of underground endurance sports.
The Guardian