| Potomac to Cassina de' Pecchi | 4,228.36 mi (6,804.89 km) |
| Potomac to Cassino | 4,560.36 mi (7,339.19 km) |
| Potomac to Castagneto Carducci | 4,359.61 mi (7,016.11 km) |
| Potomac to Castano Primo | 4,201.55 mi (6,761.75 km) |
| Potomac to Castel Bolognese | 4,372.58 mi (7,037.00 km) |
| Potomac to Castel Gandolfo | 4,499.39 mi (7,241.07 km) |
| Potomac to Castel Goffredo | 4,282.90 mi (6,892.66 km) |
| Potomac to Castel Maggiore | 4,345.48 mi (6,993.38 km) |
| Potomac to Castel Mella | 4,262.41 mi (6,859.68 km) |
| Potomac to Castel San Giorgio | 4,624.87 mi (7,443.01 km) |
| Potomac to Castel San Giovanni | 4,246.30 mi (6,833.75 km) |
| Potomac to Castel San Pietro Terme | 4,360.43 mi (7,017.44 km) |
| Potomac to Castel Volturno | 4,580.44 mi (7,371.51 km) |
| Potomac to Castelbuono | 4,704.58 mi (7,571.29 km) |
| Potomac to Casteldaccia | 4,674.31 mi (7,522.57 km) |
