12hr ultramarathons in United States in 2027

Tranquil Wekiwa Springs trails, challenging ultra course, scenic views, local wildlife, solo or relay options, festival atmosphere with on-site aid

Rugged forested loops on Whitwell Mountain with 1000 feet of elevation gain per circuit, diverse terrain, bluffs, waterfalls, and scenic vistas

Out-and-back 7.5-mile loops at Dryden Lake Park, 100-mile or 30-hour formats, basic aid, winter conditions, low-key community atmosphere

Looped 1.3 and 3.1 mile courses with flexible distance options in a 12-hour endurance format

Out-and-back on Lake Bastrop’s North-South Trailway: packed dirt singletrack, sand and rock through Lost Pines, bridges and gently rolling terrain.

Randomized trail loops through Clinton Lake State Park’s varied terrain, originating from Coneflower Campground, with 24-hour and shorter duration options

4.15-mile loop of moderately technical singletrack through hardwood forest, with rocks, roots and about 400 feet of elevation gain per lap

Team-based trail course at The Silos Barn featuring fitness and strength tasks each lap, with one participant on the trail per team at a time

24- and 48-hour record-eligible track ultras on a newly resurfaced Florida Atlantic University loop, with infield crew setup and four-hour direction changes

Repeated laps of the Great Blue Heron Loop Trail over 3, 6, or 12 hours, with individual and 12-hour relay team options

Rugged 5-mile trail loop at Hardin Farm, with about 1,000 feet of climbing per lap on repeatedly hilly terrain.

Challenging winter loops on Grandeur Peak with 2,600 feet of elevation gain per 5.8-mile circuit in the Wasatch Mountains

Trail loops in challenging winter conditions supporting air quality nonprofits and environmental education

Winter endurance loop on Grandeur Peak in the Wasatch Mountains, featuring challenging snowy conditions and views along the Wasatch Front.

Shaded woodland loops on packed sand and pine needles, gentle elevation, single- and double-track trails with convenient pavilion start and finish

Timed 6- or 12-hour format on a 5K lap loop, with hourly cutoffs and progressive elimination

Multi-day ultra event at Clay County Regional Sports Complex with ample self-crewing space, flat venue terrain, and festive community atmosphere

12-hour overnight race on a one-mile loop, with rest and refuel zone at the start area and flexible pacing for runners of all levels

Certified 1.2-mile loop with gentle elevation, 95% hard surface, scenic lake and bridge crossings, and generous time limits in Henderson, Nevada

Flat, non-technical 2-mile loop through open pasture and shaded woods on a 350-acre private family farm in Brooklet, Georgia.