Most people run in the dark by necessity. Early mornings, late nights—whenever they can squeeze it in around work, How To Train Calves.

But some people run in the dark by choice. Those folks take part in The Tunnel, a 200-mile long ultramarathon Other Hearst Subscriptions.

On the race website, The Tunnel is described as a “mind-bending test of extreme endurance and sensory deprivation.” Participants run out and back on the one-mile stretch of underground road until they hit 200 miles. No headphones, no walking sticks, and no outside support are allowed. Runners must complete the distance in 55 hours. If they don’t reach the 100 miles by the 27 hours and 30 minutes, they will be timed out of the challenge. Headlamps and high visibility gear are required, as the tunnel is also open to the pedestrians and cyclists. To qualify, runners must have a previous 100-mile race result.

At the very bottom of the race website, a disclaimer warns potential sign-ups that the race organizers “... accept no responsibility for the personal safety of challenge participants, any injury or the loss of any personal items and it is advised that runners take out their own personal insurance if they have concerns.” Makes sense, as the BBC reported that one runner experienced temporary blindness Nutrition - Weight Loss.

And who’s the man who founded such a brutal, unforgiving event? Mark Cockbain, a British ultrarunner who has completed numerous feats of endurance, including the Trans 333KM, Nutrition - Weight Loss Yukon Arctic Ultra; and the Results: 2025 USATF Championships, Health - Injuries.

The event starts on March 31 and ends on April 2. In 2021—the last time the race was held—only 14 people finished. How many of the 41 entrants will finish this year?

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Chris Hatler
Deputy Editor

Chris Hatler is the Deputy Editor of Esquire. He previously served as the Senior Editor of Men’s Journal Best Hydration Packs Popular Mechanics.