| Helensburgh to Cortona | 1,149.08 mi (1,849.26 km) |
| Helensburgh to Cosenza | 1,500.15 mi (2,414.26 km) |
| Helensburgh to Cossato | 912.75 mi (1,468.92 km) |
| Helensburgh to Costa Volpino | 951.38 mi (1,531.10 km) |
| Helensburgh to Creazzo | 1,008.44 mi (1,622.93 km) |
| Helensburgh to Crema | 965.45 mi (1,553.74 km) |
| Helensburgh to Cremona | 988.44 mi (1,590.74 km) |
| Helensburgh to Crevalcore | 1,043.64 mi (1,679.58 km) |
| Helensburgh to Crispiano | 1,455.07 mi (2,341.70 km) |
| Helensburgh to Crosia | 1,499.83 mi (2,413.74 km) |
| Helensburgh to Crotone | 1,538.01 mi (2,475.18 km) |
| Helensburgh to Cuneo | 967.02 mi (1,556.26 km) |
| Helensburgh to Cuorgne | 909.64 mi (1,463.93 km) |
| Helensburgh to Cusano Milanino | 941.18 mi (1,514.68 km) |
| Helensburgh to Cutro | 1,536.98 mi (2,473.53 km) |
