Lost Sierra Endurance Race

Downieville, United States • 25 Jul 2026

Lost Sierra Endurance Race : July 25, 2026

The Lost Sierra Endurance Race takes place in Downieville, California, in the northern Sierra Nevada. The event offers trail races through river canyons, alpine ridgelines, and remote singletrack. Distances offered are 25K, 50K, and 100K. The event includes aid stations, drop-bag and crew access points, shuttle service to the 50K start, and a post-race gathering at the finish area.

Distances

  • 100K - out-and-back, Downieville to Plumas-Eureka State Park and return
  • 50K - point-to-point, Plumas-Eureka State Park to Downieville
  • 25K - loop, starts and finishes in Downieville via divide trails

Course support, rules, and logistics

There are 5 unique aid stations; the 25K uses Aid #1, the 50K uses Aid #1-4, and the 100K uses Aid #1-5. Aid stations provide water, hydration mix, and light food; some stations offer warm food and ice. Drop bags and crew access exist for designated aid stations; 100K has multiple crew/drop-bag access points including Aid #2, Aid #4, and Aid #5, while the 50K has at least one drop-bag access at Aid #2. A shuttle from Downieville to the 50K start is available for a fee; there are no post-race shuttles for return or for pacers.

Cutoff times are set by distance: 25K - 6 hours, 50K - 10 hours, 100K - 20 hours. The 100K requires runners to carry a vest or hydration pack, a space blanket, and a headlamp. Pacers are permitted for 100K runners on the return at Aid #5 or Aid #2, with no shuttle support for pacers. Trail surface breakdown: about 70% alpine singletrack, 20% mountain bike singletrack, and 10% dirt, gravel, or paved road.

Downieville has limited lodging; the start area may be used for tent camping but is not a campground and lacks firepits, designated parking spaces, or bear boxes. The event does not offer general refunds; a rollover credit schedule is available based on cancellation timing. The Unity Initiative offers matched donation discounts for select nonprofit partners. Visit the organization's website for the most recent information.

Race information

100 km
100k
50 km
50k
25 km
25k
Visit the organization's website for the most recent information.
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