Western States 100

Western States Endurance Run
Western States Endurance Run logo patch
Date	Last weekend of June
Location	Squaw Valley, California
Event type	Ultramarathon trail run
Distance	100 miles (161 km)
Established	1977
Course records	Men: 14:46:44 (2012) Timothy Allen Olson Women: 16:47:19 (2012) Ellie Greenwood
Official site	www.wser.org

The Western States Endurance Run, known commonly as the Western States 100, is a 100-mile (161 km) ultramarathon that takes place on trails in California's Sierra Nevada Mountains annually on the last full weekend of June. The race starts at the base of the Squaw Valley ski resort and finishes at the Placer High School track in Auburn, California. The terrain is quite rugged, frequently with snow on the ground at the highest passes, and hot temperatures in the low valleys near the end of the course. Runners ascend a cumulative total of 18,090 feet (5500 m) and descend a total of 22,970 feet (7000 m) on mountain trails before reaching the finish. Because of the length of the race, the race begins at 5 a.m. and continues through the day and into the night. Runners finishing before the 30-hour overall time limit for the race receive a commemorative bronze belt buckle, while runners finishing in under 24 hours receive a silver belt buckle.

The Western States 100 is sponsored by Altra, a Utah athletic footwear company, and is one of the four 100-mile races that comprise the Grand Slam of Ultrarunning, which also includes the Vermont 100 Mile Endurance Run, the Wasatch Front 100 Mile Endurance Run in Utah, and the Leadville Trail 100 in Colorado.

The Western States Endurance Run was first completed in 1974 by Gordy Ainsleigh. Ainsleigh had finished the Western States Trail Ride (Tevis Cup) in 1971 and 1972 on horseback, but in 1973 his new horse was pulled with lameness at the 29-mile checkpoint. In 1974, with the inspiration and encouragement of Drucilla Barner, first woman to win the Tevis Cup and Secretary of the Western States Trail Foundation, Gordy joined the horses of the Western States Trail Ride to see if he could complete the course on foot. Twenty-three hours and forty-two minutes later Gordy arrived in Auburn, proving that a runner could, indeed, travel the 100 miles in one day.