The 5 100K ultramarathons in Illinois, with each one's climb, cutoff and date. Every race links to its own page, where you can see how it fits the runner you are now.
| Race | Distance | Where | Date | Climb | Cutoff |
|---|---|---|---|---|---|
| Hindsight Ultra Trail Runs | 100 KM | Dixon, IL | Sep 26, 2026 | 5,000 ft | 32 h |
| Shake Your Trail Feather Trail Run | 100 KM | Charleston, IL | Oct 17, 2026 | — | 24 h |
| Tunnel Hill 50 Mile Race | 100 KM | Vienna, IL | Nov 14, 2026 | — | 19 h |
| Shawnee Hills Trail Races | 100 KM | Ozark, IL | Aug 21, 2027 | 6,400 ft | 32 h |
| Temptation 200 Ultras | 100 KM | Forest City, IL | Sep 4, 2027 | 3,200 ft | 28.5 h |