Skyline 50k Endurance Run

Castro Valley, United States • 2 Aug 2026

Event overview

Skyline 50K Endurance Run takes place on August 2, 2026, at Lake Chabot Marina in Castro Valley, California. Organizers describe the race as one of the oldest continuously running 50k events in the United States. The event includes a half marathon option and is listed as part of the P-USATF Grand Prix and as a UTMB Index event.

Distances

  • 50K
  • 21K (Half Marathon)

Course and support

Both races start and finish at Lake Chabot Marina. The 50K follows a large loop through the East Bay Regional Parks and reaches Skyline Gate; the half returns to a looped format that also starts and finishes at the marina. Aid stations are staffed by Bay Area running groups, and a Volunteer Safety Patrol provides direction at key intersections. Training runs associated with the event are free and self-supported.

Entries, swag and policies

Bib pickup is optional; someone may pick up bibs for another entrant and bibs can be obtained on race morning. All finishers receive a race shirt, special Skyline socks, and a finisher medal. Awards are given to overall winners and three deep by age group. The race is plant-based and offers plant-based post-race food. Generally, refunds are not offered; deferrals are permitted more than 30 days before the race, with no deferrals within 30 days. Visit the organization's website for the most recent information.

Race information

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