A dedicated group of athletes has earned its place in the record books by completing a certified marathon more than 3,000 feet below the Earth’s surface. The feat has been officially recognised as the deepest marathon ever completed, setting a new Guinness World Record for an event few expected to see happen underground.
The runners navigated the subterranean course by completing repeated laps through the dimly lit tunnels, relying on headlamps and meticulous planning to stay on track. Guinness World Records later revealed the group had also achieved a second milestone, completing 11 laps for a combined underground distance of 1,082.30 metres, which translated to about 3,550 feet, securing another team record for the deepest underground marathon distance.
Runners strap headlamps on to tackle deepest marathon over 3,000 ft undergroundhttps://t.co/bfxoFBJEsa
— Guinness World Records (@GWR) March 11, 2026
Beyond the physical challenge, the event carried a charitable purpose. The team’s marathon efforts helped raise close to $1 million for charity, turning a demanding environment into a powerful fundraising platform. Organisers said the unique setting also highlighted the spirit of innovation behind the challenge, combining athletic ambition with a goal to make a difference.
By the time they completed the event, participants had not only secured two world records but also showcased what can be achieved when creative thinking meets endurance sport. Their underground run joins a growing list of unconventional athletic achievements that push the boundaries of where, and how, human performance can thrive.
