| Duncan to Foothill Farms (California) | 1,326.48 mi (2,134.77 km) |
| Duncan to Fords (New Jersey) | 1,353.34 mi (2,177.99 km) |
| Duncan to Forest (Virginia) | 1,058.78 mi (1,703.95 km) |
| Duncan to Forest Acres (South Carolina) | 967.12 mi (1,556.44 km) |
| Duncan to Forest City (Florida) | 1,049.59 mi (1,689.15 km) |
| Duncan to Forest Grove (Oregon) | 1,524.02 mi (2,452.68 km) |
| Duncan to Forest Hill (Texas) | 135.18 mi (217.56 km) |
| Duncan to Forest Hills (Michigan) | 885.39 mi (1,424.89 km) |
| Duncan to Forest Lake (Minnesota) | 785.14 mi (1,263.56 km) |
| Duncan to Forest Park (Georgia) | 778.14 mi (1,252.30 km) |
| Duncan to Forest Park (Illinois) | 745.59 mi (1,199.91 km) |
| Duncan to Forest Park (Ohio) | 808.32 mi (1,300.87 km) |
| Duncan to Forestville (Maryland) | 1,200.65 mi (1,932.25 km) |
| Duncan to Forestville (Ohio) | 812.92 mi (1,308.27 km) |
| Duncan to Forney (Texas) | 150.16 mi (241.65 km) |
