| Duncan to Clemson (South Carolina) | 858.43 mi (1,381.50 km) |
| Duncan to Clermont (Florida) | 1,038.79 mi (1,671.76 km) |
| Duncan to Cleveland (Mississippi) | 414.91 mi (667.73 km) |
| Duncan to Cleveland (Ohio) | 1,003.33 mi (1,614.70 km) |
| Duncan to Cleveland (Tennessee) | 740.69 mi (1,192.02 km) |
| Duncan to Cleveland Heights (Ohio) | 1,009.84 mi (1,625.18 km) |
| Duncan to Cliffside Park (New Jersey) | 1,373.67 mi (2,210.70 km) |
| Duncan to Clifton (Colorado) | 661.27 mi (1,064.22 km) |
| Duncan to Clifton (New Jersey) | 1,365.49 mi (2,197.55 km) |
| Duncan to Clinton (Iowa) | 654.03 mi (1,052.56 km) |
| Duncan to Clinton (Maryland) | 1,197.81 mi (1,927.69 km) |
| Duncan to Clinton (Mississippi) | 462.29 mi (743.99 km) |
| Duncan to Clinton (Utah) | 894.71 mi (1,439.89 km) |
| Duncan to Clive (Iowa) | 537.58 mi (865.15 km) |
| Duncan to Cloquet (Minnesota) | 887.92 mi (1,428.97 km) |
