| Helensburgh to Cividale del Friuli | 1,039.23 mi (1,672.49 km) |
| Helensburgh to Civita Castellana | 1,217.29 mi (1,959.04 km) |
| Helensburgh to Civitanova Marche | 1,198.46 mi (1,928.73 km) |
| Helensburgh to Civitavecchia | 1,211.99 mi (1,950.51 km) |
| Helensburgh to Civitella in Val di Chiana | 1,133.35 mi (1,823.96 km) |
| Helensburgh to Clusone | 944.16 mi (1,519.47 km) |
| Helensburgh to Coccaglio | 962.75 mi (1,549.39 km) |
| Helensburgh to Codigoro | 1,065.55 mi (1,714.84 km) |
| Helensburgh to Codogno | 977.76 mi (1,573.55 km) |
| Helensburgh to Codroipo | 1,031.82 mi (1,660.56 km) |
| Helensburgh to Cogoleto | 994.06 mi (1,599.78 km) |
| Helensburgh to Colle di Val d'Elsa | 1,118.08 mi (1,799.37 km) |
| Helensburgh to Colle Salvetti | 1,088.75 mi (1,752.18 km) |
| Helensburgh to Collecchio | 1,015.29 mi (1,633.95 km) |
| Helensburgh to Colleferro | 1,266.86 mi (2,038.81 km) |
