| 10186 | 20 Sep 26 | Catalina State Park 50-Year Trail Race and Easy 5K Trail Run | 5K/9.3M | Tucson, AZ |
| 10187 | 13 Mar 27 | Catalina Island Marathon | 5K/10K/26.2M | Avalon, CA |
| 10188 | 14 Nov 26 | Catalina Island Half Marathon | 10K/13.1M | Avalon, CA |
| 10189 | 26 Sep 26 | Cat's Tail Marathon | 26.2M | Shandaken, NY |
| 10190 | 10 Oct 26 | Cat Reman Challenge | 5K | Corinth, MS |
| 10191 | 13 Sep 26 | Cat Caper 5K | 5K | Westerville, OH |
| 10192 | 25 Oct 26 | Castle to River Run | 5K/13.1M | Garrison, NY |
| 10193 | 03 Oct 26 | Castle Rock Trail Festival | 5K/10K/13.1M/50K | Castle Rock, CO |
| 10194 | 03 Oct 26 | Castle Creek Triathlon | Sprint Duathlon/Sprint Triathlon | Morristown, AZ |
| 10195 | 07 Sep 26 | Castle 5K Run for Hope | 5K | Alliance, OH |
| 10196 | 12 Sep 26 | Cassie Hines Shoes Cancer Foundation Glow Run | 1M/5K | Utica, MI |
| 10197 | 05 Sep 26 | CassadagaMan | Olympic Triathlon/Olympic Triathlon Relay/halfiron | Cassadaga, NY |
| 10198 | 03 Apr 27 | Casino Bridge Run | 5K/10K | Biloxi, MS |
| 10199 | 20 Sep 26 | Case Creek Wagging Tails on Trails 2K & 5K Run / Walk | 2K/5K | Coal Valley, IL |
| 10200 | 12 Sep 26 | Cascade Express Marathon | 13.1M/26.2M | Snoqualmie Pass, WA |