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Skyline 50k Endurance Run

Castro Valley, United States • 2 Aug 2026

Skyline 50K Endurance Run is one of the oldest continuously running 50k races in the United States. The course starts and finishes at Lake Chabot Marina in Castro Valley, California, and follows a large loop through East Bay Regional Parks out to Skyline Gate. The event is popular with first-time ultrarunners and seasoned racers alike, thanks to robust aid-station support from Bay Area running groups and a strolling Volunteer Safety Patrol at key intersections.

It’s a plant-based race, culminating in plant-based BBQ and beer back at the marina. Runners earn a finishers medal, race shirt, and Skyline socks, with age-group and overall awards. The race is part of the USATF Grand Prix and UTMB Index events. Visit the organization's website for the most recent information.

United States California Castro Valley

Race information

Website
UTMB 50K
50 km
Skyline 50k Endurance Run
Visit the organization's website for the most recent information.
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