I Raced the Hardest Triathlon You've Never Heard Of

Mark is in Thun, Switzerland, to take on the legendary Inferno Triathlon — one of the toughest multi-sport races in the world, and one you’ve probably never heard of.

With a 3.1km lake swim, a 97km road bike, a 30km mountain bike and a 25km mountain run, the race packs a staggering 5,500m of climbing into one brutal day, finishing at 3,000m above sea level on the summit of the Schilthorn.

Watch as Mark battle cramps, a major mechanical issue and rapidly changing weather in a desperate push to make it to the finish.

00:00 Into the Inferno
01:00 About the Event + the Course
03:41 Race Morning
06:22 T1 + Onto the Bike
11:38 Kit Choice and Setup
13:33 Hitting the Climbs
16:46 Heading Off-Road on the MTB
17:18 My Canyon Lux WC
20:55 Disaster on the MTB Leg
25:38 Onto the Trail Run
29:46 The Weather Takes a Turn

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Which event do you think looks tougher? The Inferno Triathlon or the legendary Norseman? 👀 Let us know your pick in the comments! 👇

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