The Western States Endurance Run is a prestigious 100-mile ultramarathon held annually in California. It takes place in June, starting in Squaw Valley and finishing in Auburn. The race features challenging terrain, including steep climbs and rugged trails, attracting elite and amateur runners alike. Established in 1974, the event is part of the Ultra-Trail World Tour and is known for its scenic views of the Sierra Nevada mountains. Runners must complete the course within 30 hours, navigating through various checkpoints and aid stations along the way to ensure their safety and hydration.