4 Fore 30 Infinity Backyard Ultra

4 Fore 30 Infinity Backyard Ultra, held in Macks Creek, Missouri, is a Last Man Standing ultramarathon following the Backyard Ultra format. Runners cover a 4.1667-mile loop (6.7056 km) every hour, with the field shrinking as each loop is completed. The course is a loop or out-and-back and must be finished within the hour to count; no non-competitors may be on the course, and no artificial aids are allowed.

An aid station sits near the start–finish, and lighting is provided. All race profits go to the Kids’ Harbor Child Advocacy Center. Swag is awarded; bib transfers are allowed until November 1; refunds are not offered.

Nearby lodging options exist. Visit the organization's website for the most recent information.