| Potomac to Carmona | 3,778.75 mi (6,081.31 km) |
| Potomac to Cartagena | 4,003.27 mi (6,442.64 km) |
| Potomac to Cartama | 3,851.23 mi (6,197.96 km) |
| Potomac to Cartaya | 3,708.79 mi (5,968.72 km) |
| Potomac to Caspe | 3,937.69 mi (6,337.11 km) |
| Potomac to Cassa de la Selva | 4,053.17 mi (6,522.95 km) |
| Potomac to Castalla | 3,987.25 mi (6,416.86 km) |
| Potomac to Castellbisbal | 4,024.51 mi (6,476.82 km) |
| Potomac to Castelldefels | 4,030.26 mi (6,486.07 km) |
| Potomac to Castello de Ampurias | 4,051.10 mi (6,519.61 km) |
| Potomac to Castellon de la Plana | 3,975.24 mi (6,397.53 km) |
| Potomac to Castilleja de la Cuesta | 3,760.56 mi (6,052.03 km) |
| Potomac to Catarroja | 3,975.23 mi (6,397.52 km) |
| Potomac to Catral | 3,994.35 mi (6,428.29 km) |
| Potomac to Caudete | 3,968.61 mi (6,386.86 km) |
