Quotes of the Day

The term Marathon originates from the legend of an Athenian messenger named Pheidippides, who ran 25 miles home to deliver news of a great victory in the battle of Marathon, then dropped dead from exhaustion. What a wuss. For today's extreme-endurance athletes, Pheidippides' fatal exertion would be a gentle warm-up. The real challenge is found in ultramarathons—races of up to 100 km (62 miles) or even farther, often over the kind of rough terrain that would make the average jogger hang up his sneakers in horror. Ultrarunners endure cramps, blisters, dehydration and the occasional exhaustion-induced hallucination. Why? All for the pleasure of more running. "It's a desire to go beyond your comfort level and test your own boundaries," says Dean Karnazes, champion ultrarunner and author of the best-selling memoir Ultramarathon Man. "You don't get a lot of people who quit easily."

The U.S. is the center of the ultramarathon movement, with up to 15,000 runners pounding through a choice of scores of events each year. But for those in search of roads less jogged, Asia is beginning to offer its own share of long marches—from the Lake Saroma 100-km run in northern Japan to China's Gobi March, a six-stage, 250-km painfest that locals call the "Race of No Return." But the best of them all, for combining suffering and scenic beauty, is probably the annual Mongolia Sunrise to Sunset—a 100-km, waterside race around spectacular Lake Khovsgol and the surrounding national park, scheduled this year for June 29. (If you're interested in competing, details can be found at www.ultramongolia.com.)

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With its mix of deep forests, rugged hills and pristine shores, the scenery at Sunrise to Sunset is as breathtaking as the race itself—and the 60 or so runners who participate are helping to keep it that way. Co-founder Nicolas Musy, a Swiss business consultant based in China, estimates that the event has raised at least $30,000 since the first race in 1999, and much of it has gone to promoting Khovsgol as an ecotourism site. The sport has also rubbed off on the locals. Mongolia doesn't have a tradition of marathoning—in the Khans' time, if a Mongolian had to run more than a hundred paces, he jumped on a horse. But nowadays, Mongolians regularly enter—and win—the race.

As ultramarathons go, the relatively gentle Sunrise to Sunset is good for beginners—albeit beginners with a very high level of fitness. Karnazes, who commonly does 80-km training runs before going to work (he operates a natural-foods business), says the key is to extend your range. "You want to go out for five-, six-, seven-hour runs, just feeling what it's like to be on your feet that long." But the most important training is mental. Ultramarathoners must be prepared to push through the wall of exhaustion, over and over again. "The human body can only carry you so far," Karnazes concedes. "After that, the human spirit is going to take over." Here's hoping your spirit has calves of steel.

• Bryan Walsh
• Ultramarathoners are finding a new place to run wild: Mongolia