September ultramarathons in Oklahoma, United States

Single-track loop on Lake Liberty Trail with marathon and 50K options, scenic lake views, trailhead start and finish, no road running

24-hour test of endurance on paved river trails, ten 5K intervals every 2.5 hours, river crossings, night running, and sleep deprivation

Rocky, root-filled single-track loops through rolling Oklahoma woodlands with 417 feet of elevation change per loop and unique endurance challenges

Unmarked urban marathon course with map navigation, scenic city landmarks, mostly flat to gently rolling terrain, and convenience store aid stops