| South Portland to Carrollwood (Florida) | 1,272.23 mi (2,047.46 km) |
| South Portland to Carson (California) | 2,633.52 mi (4,238.24 km) |
| South Portland to Carson City (Nevada) | 2,544.20 mi (4,094.50 km) |
| South Portland to Carteret (New Jersey) | 291.58 mi (469.26 km) |
| South Portland to Cartersville (Georgia) | 1,015.55 mi (1,634.37 km) |
| South Portland to Carthage (Missouri) | 1,335.92 mi (2,149.96 km) |
| South Portland to Cary (Illinois) | 912.16 mi (1,467.97 km) |
| South Portland to Cary (North Carolina) | 706.08 mi (1,136.33 km) |
| South Portland to Casa de Oro-Mount Helix (California) | 2,606.25 mi (4,194.36 km) |
| South Portland to Casa Grande (Arizona) | 2,341.12 mi (3,767.67 km) |
| South Portland to Casas Adobes (Arizona) | 2,323.85 mi (3,739.88 km) |
| South Portland to Cascades (Virginia) | 485.39 mi (781.16 km) |
| South Portland to Casper (Wyoming) | 1,800.18 mi (2,897.11 km) |
| South Portland to Casselberry (Florida) | 1,201.03 mi (1,932.87 km) |
| South Portland to Castaic (California) | 2,630.65 mi (4,233.62 km) |
