| Potomac to Cividale del Friuli | 4,380.80 mi (7,050.22 km) |
| Potomac to Civita Castellana | 4,469.25 mi (7,192.56 km) |
| Potomac to Civitanova Marche | 4,491.25 mi (7,227.97 km) |
| Potomac to Civitavecchia | 4,449.28 mi (7,160.43 km) |
| Potomac to Civitella in Val di Chiana | 4,399.84 mi (7,080.86 km) |
| Potomac to Clusone | 4,241.44 mi (6,825.94 km) |
| Potomac to Coccaglio | 4,253.01 mi (6,844.57 km) |
| Potomac to Codigoro | 4,368.54 mi (7,030.49 km) |
| Potomac to Codogno | 4,254.42 mi (6,846.82 km) |
| Potomac to Codroipo | 4,366.55 mi (7,027.28 km) |
| Potomac to Cogoleto | 4,233.55 mi (6,813.24 km) |
| Potomac to Colle di Val d'Elsa | 4,374.99 mi (7,040.87 km) |
| Potomac to Colle Salvetti | 4,339.83 mi (6,984.28 km) |
| Potomac to Collecchio | 4,289.88 mi (6,903.90 km) |
| Potomac to Colleferro | 4,515.97 mi (7,267.75 km) |
