The Run with the Horses Marathon is always on the 3rd weekend of August. The race is held in conjunction with the annual River Festival which kicks off that Friday with a cajun shrimp boil, homemade/handmade craft vendors, beer gardens, a band, food trucks and FIREWORKS!  All the races are in front of the pavilion at Expedition Island.

Previous runners described the course as challenging and rewarding. This is a high plains desert, there will be no shade trees after you leave the city streets. Many runners stop and take photos of the vistas and any wild horses and other wildlife they encounter. This is an out and back course, at the halfway point of each respective race you will turn around and return to Green River to the Expedition Island.