| Duncan to Central Point (Oregon) | 1,449.67 mi (2,333.02 km) |
| Duncan to Centralia (Illinois) | 560.23 mi (901.61 km) |
| Duncan to Centralia (Washington) | 1,549.45 mi (2,493.60 km) |
| Duncan to Centreville (Virginia) | 1,170.25 mi (1,883.34 km) |
| Duncan to Ceres (California) | 1,300.60 mi (2,093.12 km) |
| Duncan to Cerritos (California) | 1,150.30 mi (1,851.22 km) |
| Duncan to Chalco (Nebraska) | 469.04 mi (754.85 km) |
| Duncan to Chalmette (Louisiana) | 562.74 mi (905.64 km) |
| Duncan to Chambersburg (Pennsylvania) | 1,172.27 mi (1,886.59 km) |
| Duncan to Chamblee (Georgia) | 778.99 mi (1,253.66 km) |
| Duncan to Champaign (Illinois) | 654.53 mi (1,053.36 km) |
| Duncan to Champlin (Minnesota) | 772.40 mi (1,243.07 km) |
| Duncan to Chandler (Arizona) | 802.82 mi (1,292.01 km) |
| Duncan to Chanhassen (Minnesota) | 749.05 mi (1,205.48 km) |
| Duncan to Channahon (Illinois) | 708.27 mi (1,139.86 km) |
