Zane Grey 50-Mile Endurance Run
Pine to Christopher Creek, Arizona
The Highline Trail through Tonto National Forest covers some rough, rocky, exposed terrain. The elevation hovers between six- and seven-thousand feet, with runners climbing more than 11 thousand in total under the blazing Arizona sun. Because this trek is often touted as the most difficult 50-miler in the country, it isn't recommended for first-time ultramarathoners. "Race management would like to avoid having to send out search and rescue to retrieve runners on the course," reads the event's website. "We've had to do this several times in the past."
Ultra-Trail du Mont-Blanc
The Mont Blanc massif
The North Face's UTMB traverses the Mont Blanc massif, which straddles the area where France, Switzerland, and Italy meet. "It's the hardest thing I've ever done" admits Outside assistant editor and ultrarunner Meaghen Brown. "It attracts the most elite runners in the world," she adds, "who find themselves scrambling through the mountains, often over a period of two full days." The race spans about 104 miles, gaining a cumulative 6 more in height along the way, while traversing ten mountain passes. Participants who want just a taste of the fun can take advantage of the three shorter races and relay on offer. But Brown recommends going for the gusto, if you feel you can, explaining that, "despite tearing your body apart," the event never ceases to amaze. "The aid stations have dark chocolate, locals greet you with accordions and high fives, and dropping off the mountain pass into Courmayer at sunrise is one of the most profoundly beautiful things you'll ever see."
Rocky Raccoon 100
If you're looking for an "easy" hundred, Rocky Raccoon is your best bet. The course is flat and fast—five 20-mile loops with minimal elevation gain. Although you won't have to worry about rocks, be mindful of tree roots, which are plentiful and can trip up even the most accomplished athlete. "Rocky Raccoon combines grand old Texas hospitality and the usual ultrarunner bonhomie," says race director Joe Prusaitis. "Our multiloop format, with its out-and-back sections, provides constant reacquaintance so, by race's end, everyone's part of the same family. Add in the best aid-station volunteers on the planet, and we've got the Woodstock for runners."
The Rut 50K
Big Sky, Montana
The Rut 50K's distinctive blend of challenging and varied turf makes it one of the more difficult ultra races out there, but there's a payoff. Participants run everything from jeep roads to forested singletrack to alpine ridge lines, even summiting Lone Peak. Over the course's 31 miles, runners will gain 10,000 feet and see some of Montana's most beautiful backcountry. Uniquely spectacular terrain is what sets the Rut apart from other U.S. races, according to director Mike Foote, who emphasizes its "technical, exposed, alpine, steep, and severe" nature. For the faint of heart, organizers offer vertical kilometer and 12K races—but it's worth gearing up for the whole enchilada. Registration maxes out at 500 people, so sign on early.
Bighorn Mountain Wild and Scenic Trail Run
Bighorn offers 30K, 50K, and 50-mile events—but the 100-mile option is especially appealing, trotting out all there is to love about Wyoming wilderness and the Bighorn Mountains. According to Bighorn alumna Meaghen Brown, participants feel like they're crashing a scene in The Sound of Music, tackling rugged mountain trails at elevations of up to 10,000 feet as they're showered with love by the hosts of this old-school ultra. "The aid stations are really tough to get to, so most of them are manned by chubby old cowboys, who stay up late cooking bacon and cheering you on with more enthusiasm than a stage mother," Brown says. "And there's a rogue aid station, run by a group of local kids a mile from the finish, that hands out life-saving Otter Pops to exhausted runners."
Western States Endurance Run
Squaw Valley to Auburn, California
Often called the Western States 100, this is the ultrarunner's version of the Boston Marathon—the oldest, most prestigious race of its kind, the event requires that you qualify to compete, which is hard as hell to do. Held along a portion of the Western States Trail, the course has participants climb 2,550 vertical feet in its first four and a half miles. Runners then ascend another 15,540 feet before descending 22,970 more, en route to Auburn. "I heard about Western States the way Little Leaguers hear about Babe Ruth," seven-time WS100 winner Scott Jurek writes in his book, Eat & Run. "People spoke of its difficulties, how it broke spirits as well as bodies." Those who manage to finish the slog in under 24 hours are given a sterling-silver belt buckle that reads 100 MILES, ONE DAY. In 2013, 277 of the 383 starters finished the race, with 95 receiving the coveted buckle.