Mammoth Trail Fest
Mammoth Lakes, United States • 25-27 Sep 2026
Event
Mammoth Trailfest is a multi-day trail running festival held in Mammoth Lakes, California on September 25-27, 2026. The event weekend includes multiple races and community festival programming located around the Village at Mammoth Plaza. Distances and events include:
- 50K
- 26K
- Dragon’s Back Ascent
- Mammoth Triple
- tenkay
- Kids 1K
The festival offers professional chip timing with on-course splits for the 50K and 26K, live timing, finishers medals, event swag, aid stations, free town shuttles, and gondola access to summit aid points (gondola ticketing and operating hours subject to event updates).
Race information
Course marking uses colored flags, ribbons, and signs (50K - purple; 26K - orange; tenkay - green; dragon’s back - orange). Aid station provisioning: 50K has six aid stations, 26K has four, tenkay has one, and Dragon’s Back Ascent has no aid. Cutoffs are published for each race (for example, 50K - 12 hours; 26K - 7 hours; Dragon’s Back Ascent - 2.5 hours). The event is cup-less; runners must carry personal bottles or collapsible cups.
Safety and rules: poles are allowed, pacers are not permitted, crews are allowed with location restrictions, littering and course cutting may result in disqualification, and headphones are discouraged. Required gear is not mandated but recommended items include a cell phone, at least 1 L of fluids, extra layers, and an emergency blanket; organizers may enforce a Cold Weather Kit if conditions require. Prize money is offered for top overall finishers and age-group awards are given by chip time. Visit the organization's website for the most recent information.