| Duncan to Anoka (Minnesota) | 775.01 mi (1,247.25 km) |
| Duncan to Ansonia (Connecticut) | 1,427.49 mi (2,297.33 km) |
| Duncan to Antelope (California) | 1,327.39 mi (2,136.23 km) |
| Duncan to Anthem (Arizona) | 811.93 mi (1,306.67 km) |
| Duncan to Antioch (California) | 1,347.30 mi (2,168.27 km) |
| Duncan to Antioch (Illinois) | 763.19 mi (1,228.24 km) |
| Duncan to Apache Junction (Arizona) | 783.45 mi (1,260.85 km) |
| Duncan to Apex (North Carolina) | 1,077.69 mi (1,734.37 km) |
| Duncan to Apollo Beach (Florida) | 1,028.71 mi (1,655.55 km) |
| Duncan to Apopka (Florida) | 1,043.64 mi (1,679.58 km) |
| Duncan to Apple Valley (California) | 1,096.19 mi (1,764.15 km) |
| Duncan to Apple Valley (Minnesota) | 748.14 mi (1,204.02 km) |
| Duncan to Appleton (Wisconsin) | 842.28 mi (1,355.53 km) |
| Duncan to Arbutus (Maryland) | 1,214.05 mi (1,953.83 km) |
| Duncan to Arcadia (California) | 1,146.10 mi (1,844.47 km) |
