Ruth Anderson Memorial Endurance Run
Lakeshore, United States • 11 Oct 2025
Ruth Anderson Memorial Endurance Run : event details
The Ruth Anderson Memorial Endurance Run is scheduled for October 11, 2025 and marks the 38th running since 1986. The event is held in San Francisco, California. Distances offered include:
- 100 km
- 50 miles
- 50 km
The race was first held in 1986. It was not held in 1999 and the 2020 edition was cancelled due to COVID-19. Course records and age-group results are maintained for the 100k, 50-mile, and 50k distances.
Course and logistics
Race headquarters and the start/finish are at Lake Merced Blvd. and Sunset Blvd., San Francisco. The course is a 4.475-mile loop on a paved bike path with dirt shoulders. Aid is provided once per loop at the start/finish area. Total climb per full course set is listed as 2,488 feet with total descent 2,555 feet; high point is 94 feet and low point is 29 feet; start and finish elevation is 72 feet. The 50-mile race has intermediate cutoffs: 7 laps (31.1 miles) by 7.5 hours and 10 laps (44.5 miles) by 11 hours into the race. Chip timing is provided by Coastal Trail Runs. The 50K and 50M courses are USATF certified. Race-day registration is available for a $10 additional fee if the race is not filled. Visit the organization's website for the most recent information.