| Duncan to Commerce (California) | 1,153.83 mi (1,856.90 km) |
| Duncan to Commerce City (Colorado) | 529.17 mi (851.62 km) |
| Duncan to Compton (California) | 1,159.08 mi (1,865.35 km) |
| Duncan to Comstock Park (Michigan) | 881.43 mi (1,418.52 km) |
| Duncan to Concord (California) | 1,358.46 mi (2,186.23 km) |
| Duncan to Concord (Missouri) | 501.38 mi (806.89 km) |
| Duncan to Concord (New Hampshire) | 1,531.39 mi (2,464.53 km) |
| Duncan to Concord (North Carolina) | 979.19 mi (1,575.86 km) |
| Duncan to Conneaut (Ohio) | 1,068.32 mi (1,719.29 km) |
| Duncan to Connersville (Indiana) | 787.03 mi (1,266.61 km) |
| Duncan to Conroe (Texas) | 324.20 mi (521.75 km) |
| Duncan to Converse (Texas) | 348.39 mi (560.69 km) |
| Duncan to Conway (Arkansas) | 311.47 mi (501.26 km) |
| Duncan to Conway (Florida) | 1,060.89 mi (1,707.33 km) |
| Duncan to Conway (South Carolina) | 1,078.46 mi (1,735.62 km) |
