Wasatch began in its early years as a challenge for some local runners who were inspired by Western States, the first of modern-day western 100s. One year, no one finished. Now 29 years old, the race has matured into a smooth-running event attracting runners from across the world.
Wasatch gains cumulatively 26,000 feet in elevation as it traverses the Wasatch Front, commanding vistas of basin and range country, the Great Salt Lake, steep canyons, broad plateaus, and craggy peaks. Altitude ranges from 4,700 to 10,460 feet, and temperatures range from 80s in the shade during the day to 30s on the high ridges at night. The fastest runners typically finish the race in 20 hours or so, while the field is given 36 hours to finish the race.
For many years Wasatch was regarded as the toughest 100-miler, but with the advent of the Hardrock 100 in Colorado, this has been thrown into some dispute. Apologists for Wasatch note that Hardrock has a 48-hour cutoff, and therefore is in a different category of event (a quasi multi-day). Both races are undeniably very difficult and pose their own challenges.
Runners who complete Wasatch along with the Western States Endurance Run in Northern California, the Vermont 100 Mile Endurance Run in Vermont, and the Leadville Trail 100 in Colorado all in the same summer achieve the Grand Slam of Ultrarunning and are awarded with a sculpted eagle-head trophy. Wasatch is the final of the four races, and, as a result, the Grand Slam award is presented at the post-race Awards Banquet.
Wasatch is a part of the Western Slam (Wasatch, the Leadville 100, the Western States Endurance Run, and the Angeles Crest 100), and an optional part of the Rocky Mountain Slam (Hardrock 100, plus three of four of Wasatch, the Bighorn 100, the Bear 100 Mile Endurance Run, or Leadville).