Ruth Anderson Memorial Endurance Run

OCT
10
2026
Endurance races on a 4.5 mile loop around Lake Merced in San Francisco on 10/10/2026, featuring 50K, 50 mile, and a 4.5 mile Coastal Testing race.
Sat 10 Oct 2026
50 miles 50 kilometers 5 miles

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Ruth Anderson Memorial Endurance Run

The event takes place in San Francisco at the Lake Merced Blvd Parking Lot (North) on 10/10/2026. The listed races use a measured 4.5 mile loop around Lake Merced as the course.

All races are assigned an event type and a distance. Distances offered include:

  • 50K
  • 50 Miles
  • Coastal Testing : 4.5 Miles

Registration for the listed events is free. The two longer races are classified as ultramarathon events and the shorter Coastal Testing race is listed as a running race. The setting is the Lake Merced loop, providing a repeated‑lap format for competitors and support personnel to plan around the single measured loop. Visit the organization's website for the most recent information.

50 mi
50mi
50 km
50k
5 mi
Coastal Testing

Events nearby

PA-USATF cross-country races at China Camp State Park on Oct 11, 2026, with a roughly 4.25 mile rolling single track course and three race divisions.
Scenic coastal 5K, 10K, half marathon and kids run in Half Moon Bay that raises funds for Senior Coastsiders; every participant receives a pumpkin.
Trail races at Redwood Regional Park on October 24, 2026 with 35K, half marathon and 10K routes, chip timing, marked trails, cupless aid stations, and limited field size.
A women’s trail half in the Marin Headlands covering 13.6 miles and 2,156 feet of climbing with aid stations, shuttle service, training support, childcare grants, and a $25,000 prize purse.
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