| Duncan to Cullman (Alabama) | 632.20 mi (1,017.43 km) |
| Duncan to Culpeper (Virginia) | 1,136.72 mi (1,829.37 km) |
| Duncan to Culver City (California) | 1,167.64 mi (1,879.14 km) |
| Duncan to Cumberland (Maryland) | 1,110.94 mi (1,787.89 km) |
| Duncan to Cupertino (California) | 1,359.54 mi (2,187.97 km) |
| Duncan to Cutler Bay (Florida) | 1,217.73 mi (1,959.76 km) |
| Duncan to Cutlerville (Michigan) | 873.07 mi (1,405.07 km) |
| Duncan to Cuyahoga Falls (Ohio) | 1,002.71 mi (1,613.71 km) |
| Duncan to Cypress (California) | 1,149.08 mi (1,849.27 km) |
| Duncan to Cypress Gardens (Florida) | 1,058.08 mi (1,702.82 km) |
| Duncan to Cypress Lake (Florida) | 1,100.04 mi (1,770.35 km) |
| Duncan to D'Iberville (Mississippi) | 595.75 mi (958.77 km) |
| Duncan to Dakota Ridge (Colorado) | 529.94 mi (852.86 km) |
| Duncan to Dale City (Virginia) | 1,173.38 mi (1,888.37 km) |
| Duncan to Dallas (Georgia) | 747.94 mi (1,203.69 km) |
