Fat Ox

The Fat Ox endurance run, held on November 20, 2026, in Goodyear, AZ, offers a unique opportunity for ultrarunners to test their limits across a wide range of distances, including 48-hour, 24-hour, 100-mile, 100-kilometer, 12-hour, 50-mile, 50-kilometer, and 6-hour events. Set against the scenic Estrella foothills at Estrella Mountain Regional Park, this race delivers a fast and runnable experience on a USATF-certified 0.988178-mile concrete loop. The course is flat with minimal elevation gain, making it ideal for those chasing personal bests or tackling their first ultra. Typical race day conditions in late November feature comfortable highs around 74°F and lows around 49°F, with a low 2% chance of precipitation.

What began as an "ultra-experiment" for a college thesis on fat oxidation, the Fat Ox has evolved into a premier fixed-time festival, known for its professional organization by Aravaipa Running. Runners will appreciate the highly accessible and fully stocked aid station located directly on the course, passed with every lap. This 24-hour aid station provides not only traditional ultra staples but also prepared breakfast, lunch, and dinner, alongside convenient water refill and chilled water stations. The start/finish area near Ramadas 8 & 9 also allows participants to set up their own personal aid stations, pop-up tents, and chairs right along the loop for ultimate convenience.

Embrace the challenge of running day and night, experiencing breathtaking Arizona sunrises and sunsets. While the course is well-marked, runners planning to continue through the night should be prepared with their own headlamps or flashlights, as there is no artificial lighting along the entire loop. With its flat profile, comprehensive support, and the option to run for a set time or distance, the Fat Ox is a compelling event for both seasoned ultrarunners and those looking to discover their inner animal in a supportive and well-managed environment.