Once a race passes the standard 26.2-mile marathon distance, an entirely different sport begins — one built on self-sufficiency, elevation and, often, running through the night.
The Sport’s Crown Jewel
The Ultra-Trail du Mont-Blanc, held annually in Chamonix, France, circles the Mont Blanc massif across roughly 106 miles and more than 32,000 feet of elevation gain, passing through France, Italy and Switzerland in a single race. It’s widely regarded as trail running’s most prestigious single event and anchors the broader UTMB World Series, a global qualifying structure we cover in our international trail running championships guide.
America’s Original 100-Miler
- The Western States 100, run through California’s Sierra Nevada, is widely considered the oldest and most prestigious 100-mile trail race in the United States
- Entry is famously difficult, decided through a lottery weighted by qualifying finishes at other sanctioned ultras
- Summer heat through the canyon sections is often as significant a competitor as the terrain itself
Road Ultras With History
Not every major ultra is run on trails. South Africa’s Comrades Marathon, run between Durban and Pietermaritzburg, has been contested since 1921 and alternates direction each year between an “up” run and a “down” run, covering roughly 90 kilometers on paved roads. Greece’s Spartathlon, meanwhile, retraces the route of the ancient messenger Pheidippides across 246 kilometers from Athens to Sparta, with a strict 36-hour cutoff that eliminates the majority of starters.
Why Ultras Keep Growing
Interest in ultra distance racing has grown alongside trail running generally, drawing runners who have completed road majors and are looking for the next challenge, a progression we touch on in our World Marathon Majors guide. For readers curious about the shorter, faster end of the trail spectrum, our trail running championships guide covers that side of the sport in full. Whichever distance you choose to follow, ultrarunning’s culture of camaraderie between competitors remains one of its most distinctive features, and one reason the sport keeps attracting newcomers from road running.