Woman dies after collapsing during grueling Cocodona 250 ultramarathon in Arizona

A woman in her 40s died after collapsing at a trailhead in the Groom Creek community south of Prescott, turning one of the nation’s most punishing ultramarathons into a test of how much risk extreme racing can bear.

Race organizers and the Yavapai County Sheriff’s Office confirmed the death Tuesday, May 5, during the 2026 Cocodona 250. First responders treated the runner after she collapsed on the course, and Cocodona 250 co-director Erika Snyder said the woman’s name would not be released at the request of her relatives.

The 250-mile race began Monday, May 4, and was scheduled to finish Saturday, May 9. Runners have 125 hours to complete a route that runs from Black Canyon City to Flagstaff and threads through Crown King, Prescott, Jerome and Sedona, with more than 38,000 feet of climbing. The event, organized by Arizona-based Aravaipa Running, is built around endurance, navigation and survival over terrain that shifts from desert to mountain trails.

This year’s field included roughly 395 to 404 runners in the 250-mile event, depending on how broader event entries are counted. The Cocodona week also includes 125-mile, 100-mile, 80-mile and 40-mile races, underscoring how deeply the event has embedded itself in the state’s endurance scene. Rachel Entrekin won the 2026 women’s and overall title in 56 hours, 9 minutes and 48 seconds, setting a course record.

Organizers said the race would continue in the runner’s honor, asking participants and crew to carry her memory on the trail. The fatality puts a stark human edge on a sport that has grown quickly worldwide but still depends on a delicate balance of preparation, course monitoring and medical response when athletes push far beyond ordinary marathon limits.

Deaths in ultramarathons are described by organizers as very rare relative to participation, but the sport’s history includes grim exceptions. The Associated Press has noted the 2021 ultramarathon in northwestern China, where freezing rain and high winds were linked to 21 runner deaths. In Arizona, where heat, elevation and isolation can all become hazards, the latest death is likely to intensify scrutiny of race oversight and emergency response across the ultramarathon world.