| Duncan to Crawfordsville (Indiana) | 714.50 mi (1,149.88 km) |
| Duncan to Crest Hill (Illinois) | 720.79 mi (1,160.00 km) |
| Duncan to Crestview (Florida) | 709.52 mi (1,141.86 km) |
| Duncan to Crestwood (Illinois) | 738.97 mi (1,189.25 km) |
| Duncan to Crestwood (Missouri) | 502.02 mi (807.92 km) |
| Duncan to Creve Coeur (Missouri) | 502.86 mi (809.28 km) |
| Duncan to Crofton (Maryland) | 1,212.36 mi (1,951.11 km) |
| Duncan to Crossville (Tennessee) | 733.41 mi (1,180.31 km) |
| Duncan to Crowley (Louisiana) | 440.26 mi (708.54 km) |
| Duncan to Crowley (Texas) | 139.43 mi (224.39 km) |
| Duncan to Crown Point (Indiana) | 745.53 mi (1,199.82 km) |
| Duncan to Crystal (Minnesota) | 764.29 mi (1,230.01 km) |
| Duncan to Crystal Lake (Illinois) | 742.04 mi (1,194.20 km) |
| Duncan to Cudahy (California) | 1,155.90 mi (1,860.24 km) |
| Duncan to Cudahy (Wisconsin) | 793.24 mi (1,276.59 km) |
