Skyline 50k Endurance Run

Castro Valley, United States • 3 Aug 2025

The Skyline 50K Endurance Run, held annually in August at Lake Chabot Marina in Castro Valley, California, is one of the longest-running 50K races in the state and among the oldest in the U.S. The course features a large loop through the scenic East Bay Regional Parks, reaching Skyline Gate. Known for its welcoming atmosphere, the race is ideal for first-time ultrarunners and competitive for veterans.

Aid stations are well-supported by local running groups, and volunteers provide guidance and encouragement along the route. The event concludes with a plant-based BBQ and beer at the marina, promoting a friendly, community-focused experience. It is part of the USATF Grand Prix and a UTMB Index race. Visit the organization's website for the most recent information.

Race information

UTMB 20K UTMB 50K
50 km
50k
21 km
21k
Visit the organization's website for the most recent information.
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