| South Portland to Chivasso | 3,700.29 mi (5,955.05 km) |
| South Portland to Ciampino | 4,022.40 mi (6,473.42 km) |
| South Portland to Cicciano | 4,137.81 mi (6,659.16 km) |
| South Portland to Cingoli | 3,991.54 mi (6,423.76 km) |
| South Portland to Cinisello Balsamo | 3,745.20 mi (6,027.31 km) |
| South Portland to Cinisi | 4,182.51 mi (6,731.10 km) |
| South Portland to Cirie | 3,686.54 mi (5,932.91 km) |
| South Portland to Ciro Marina | 4,313.19 mi (6,941.41 km) |
| South Portland to Cislago | 3,731.28 mi (6,004.91 km) |
| South Portland to Cisterna di Latina | 4,040.09 mi (6,501.90 km) |
| South Portland to Cisternino | 4,272.21 mi (6,875.45 km) |
| South Portland to Citta di Castello | 3,946.52 mi (6,351.31 km) |
| South Portland to Citta Sant'Angelo | 4,058.49 mi (6,531.50 km) |
| South Portland to Cittadella | 3,850.08 mi (6,196.11 km) |
| South Portland to Cittanova | 4,308.11 mi (6,933.23 km) |
