Fat Ox Endurance Runs

Fat Ox Endurance Runs, staged at Estrella Mountain Regional Park in Goodyear, Arizona, is a fixed-time ultramarathon festival offering 48-, 24-, 12-, and 6-hour options, plus 100 Mile, 100K, 50 Mile, and 50K races. Runners navigate a USATF-certified 0.988-mile concrete loop encircling the park’s turf area, with on-course aid and a timing tent; the loop is clearly marked with cones and flags. The event doubles as the USATF 24-Hour Championship (2025), with prize money for top finishers.

Pacers are not allowed; camping and spectating areas are available, and lights are recommended for night runs. On-site EMT support is provided. Visit the organization's website for the most recent information.