Ultramarathons in Illinois, United States

Half-mile pine forest loop in Lowell Park, continuous 6, 12, or 24-hour format with self-supported setup and solo or team options

Scenic Illinois River trails with 100 mile, 100k, and 50k options; roughly 23,500 feet of elevation gain and rustic woodland terrain at Camp Wokanda

Challenging looped course through wooded ridges and river valley along Illinois River Bluff Trail, with significant elevation gain and summer heat.

33.5-mile loop through seven western suburbs, largely on bike paths, with a steady runnable surface and point-to-point feel

Loop course through scenic park grounds with grass, gravel, and paved paths; aid stations and crew support at start and finish area

Looped park course on grass, gravel, and pavement with clockwise laps from the Laury Barn

Timed 3- or 6-hour run on a 1-mile loop around Watershed Nature Center, evening hours requiring a light source, limited to 140 participants

50-mile and 40-mile loop course through mature woodland, rolling terrain, and wide, runnable trails at Deer Grove East Forest Preserve

Looped course through Shawnee National Forest featuring 80% single-track dirt, creek crossings, rocky terrain, waterfalls, and 3200 ft elevation per loop.

Crushed gravel, dirt, and wood-chip trails winding through forests and fields with minimal elevation gain, two bridge crossings each lap, and riverbank views

Challenging 12-hour last runner standing on a 4.1-mile rugged trail loop amid summer heat at Comlara parks, testing endurance, pacing, and strategy

Multi-loop ultramarathon offering official finishes and awards at 50K, 100K, 150K, or 200K; progressive distances with tiered medallion and buckle rewards

50K trail race with Triple Crown options up to 85K, touring wooded park trails from Red Oak picnic area in Rock Cut State Park

Scenic 1-mile paved loop in a 58-acre city park, rotating hourly challenges, 6- or 12-hour format, solo or relay options, central aid station and vendor

4-mile loop on Boyscout Trail with 342 feet of elevation gain per lap, rugged terrain, and relentless hills at Ferne Clyffe State Park

50K trail course with dirt, rocks, roots, climbing, gravel, and occasional pavement; varied terrain with elevation changes and technical footing.

8-hour ultra with flexible pacing on a 1.65-mile limestone and asphalt loop, featuring flat stretches, steep climbs, and rolling hills at Limestone Park

7.85-mile loop from Meadows Park with singletrack, grassy meadows, and gravel; moderate elevation gain totaling 6,200 feet over the 100-mile distance