| Boulder to Cortona | 5,479.09 mi (8,817.75 km) |
| Boulder to Cosenza | 5,831.03 mi (9,384.13 km) |
| Boulder to Cossato | 5,233.81 mi (8,423.00 km) |
| Boulder to Costa Volpino | 5,288.11 mi (8,510.39 km) |
| Boulder to Creazzo | 5,349.83 mi (8,609.73 km) |
| Boulder to Crema | 5,296.27 mi (8,523.52 km) |
| Boulder to Cremona | 5,319.72 mi (8,561.25 km) |
| Boulder to Crevalcore | 5,378.67 mi (8,656.14 km) |
| Boulder to Crispiano | 5,796.99 mi (9,329.35 km) |
| Boulder to Crosia | 5,835.13 mi (9,390.73 km) |
| Boulder to Crotone | 5,872.66 mi (9,451.13 km) |
| Boulder to Cuneo | 5,268.17 mi (8,478.30 km) |
| Boulder to Cuorgne | 5,224.01 mi (8,407.24 km) |
| Boulder to Cusano Milanino | 5,270.08 mi (8,481.38 km) |
| Boulder to Cutro | 5,870.63 mi (9,447.87 km) |
