The Mammoth

The Mammoth : Mammoth Lakes, CA

The Mammoth is a loop footrace in Mammoth Lakes, California, scheduled for October 2, 2026 and organized by trailfest. The route circumnavigates a roughly 760,000-year-old caldera and begins and ends in Mammoth Lakes. The course passes alpine lakes, abandoned mines, areas of fall foliage, dense pine forests, the Glass Mountains, high desert sage and expanses of volcanic rock. Runners traverse the world’s largest continuous Jeffrey pine forest and the tufa towers of Mono Lake, and the route includes summits of Mammoth Mountain that reach 11,053 feet.

The event operates on permitted National Forest lands under special use permission from the Forest Service. The organizer plans to start about 250 participants and maintains a waitlist; reserved spots are released to the waitlist as they become available. Early bird pricing was listed at $1,595 through February 28; a later price listing shows $1,894.23 and current entry availability is marked as sold out.

Prize money is offered for male and female podiums: $5,000 for first, $3,000 for second, and $2,000 for third. Key event dates include mandatory check-in on October 1, the race on October 2, first finishers expected October 4, an awards ceremony on October 5, and a village cutoff on October 6 with a maximum race duration of 108 hours. Drop bags must be collected by October 7; unclaimed bags will be donated.

The organizer may cancel or postpone the event for force majeure or permit revocation. Refund and deferral policies vary by withdrawal date. Visit the organization's website for the most recent information.