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UltraQualification required

Western States 100-Mile Endurance Run

The world's oldest 100-mile trail race, from Squaw Valley to Auburn through the Sierra Nevada.

Location

Squaw Valley to Auburn, California

When

Last full weekend of June

Distance

161 km

Elevation Gain

5,500 m

Field Size

~369 athletes

Course Highlights

  • Emigrant Pass (8,750 feet) in the opening miles
  • Sierra Nevada high country
  • American River canyon crossings
  • Extreme heat in the canyons (100+ degrees)
  • Finish at Placer High School track in Auburn
  • No Hands Bridge in the final miles

The Course

The Western States 100 begins at the base of the Squaw Valley ski resort (now Palisades Tahoe) and immediately climbs to Emigrant Pass at 8,750 feet, often through snow in the early-season conditions. The opening miles traverse the high country with stunning Sierra Nevada views before descending into the American River canyon system.

The middle section of the course follows historic mining trails through deep canyons, crossing the American River at multiple points. The terrain is rugged single-track trail, with technical footing, river crossings, and relentless climbs out of canyon bottoms. Temperatures in the canyons can exceed 110 degrees Fahrenheit by midday, making the middle miles a survival test as much as a running event.

The final 20 miles feature the iconic river crossings and the long, dusty descent into Auburn. Runners pass through the no Hands Bridge area and follow the trail along the American River before the final climb to the Placer High School track, where the finish line awaits. The 30-hour cutoff means many athletes will finish in the dark, headlamps piercing the Sierra night, in one of ultrarunning's most emotional finishes.

History

The Western States 100 traces its origins to the Tevis Cup, a 100-mile horse ride from Squaw Valley to Auburn established in 1955. In 1974, Gordy Ainsleigh became the first person to complete the course on foot in under 24 hours after his horse was pulled from the ride. His run inspired the first official foot race in 1977.

Western States has since become the most prestigious 100-mile trail race in the world. The silver belt buckle awarded to sub-24-hour finishers and the bronze buckle for sub-30-hour finishers are among the most coveted prizes in ultrarunning. The race is limited to 369 starters, selected through a weighted lottery system.

How to Train for Western States 100

Train in extreme heat

Canyon temperatures exceeding 100 degrees are the race's biggest challenge. Begin heat acclimation at least two weeks before the race using sauna protocols and hot-weather running. Your body's ability to cool itself will determine your success.

Build massive vertical gain capability

With 18,000 feet of climbing and 23,000 feet of descent, your legs must handle enormous vertical. Include weekly runs with 5,000+ feet of climbing and practice power hiking on steep terrain. Back-to-back long days in the mountains are essential.

Practice crew and pacer logistics

Western States allows crew support at designated aid stations and pacers for the final 38 miles. Recruit experienced crew and pacers and practice your logistics. Efficient aid station stops can save significant time over 100 miles.

Enter the lottery early and often

Getting into Western States requires entering a lottery, with improved odds for each consecutive year of unsuccessful applications. Enter annually and build your ultrarunning resume with qualifying races to be ready when your name is drawn.

Qualification

Runners must complete a qualifying ultramarathon within the previous year. Entry is then determined by a weighted lottery, with odds increasing for each year of unsuccessful application.

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