| Duncan to Cold Springs (Nevada) | 1,262.53 mi (2,031.85 km) |
| Duncan to Coldwater (Michigan) | 866.49 mi (1,394.48 km) |
| Duncan to Colesville (Maryland) | 1,195.91 mi (1,924.64 km) |
| Duncan to College (Alaska) | 2,928.41 mi (4,712.82 km) |
| Duncan to College Park (Georgia) | 772.01 mi (1,242.43 km) |
| Duncan to College Park (Maryland) | 1,198.70 mi (1,929.12 km) |
| Duncan to College Station (Texas) | 289.22 mi (465.46 km) |
| Duncan to Collegedale (Tennessee) | 730.72 mi (1,175.98 km) |
| Duncan to Colleyville (Texas) | 122.32 mi (196.85 km) |
| Duncan to Collierville (Tennessee) | 467.74 mi (752.75 km) |
| Duncan to Collinsville (Illinois) | 523.51 mi (842.51 km) |
| Duncan to Colonia (New Jersey) | 1,353.93 mi (2,178.94 km) |
| Duncan to Colonial Heights (Virginia) | 1,161.63 mi (1,869.46 km) |
| Duncan to Colonial Park (Pennsylvania) | 1,221.46 mi (1,965.75 km) |
| Duncan to Colorado Springs (Colorado) | 482.33 mi (776.24 km) |
