| Sioux City to Cividale del Friuli | 4,956.55 mi (7,976.79 km) |
| Sioux City to Civita Castellana | 5,099.66 mi (8,207.11 km) |
| Sioux City to Civitanova Marche | 5,100.37 mi (8,208.25 km) |
| Sioux City to Civitavecchia | 5,086.20 mi (8,185.44 km) |
| Sioux City to Civitella in Val di Chiana | 5,021.13 mi (8,080.73 km) |
| Sioux City to Clusone | 4,842.59 mi (7,793.39 km) |
| Sioux City to Coccaglio | 4,858.19 mi (7,818.50 km) |
| Sioux City to Codigoro | 4,969.32 mi (7,997.35 km) |
| Sioux City to Codogno | 4,866.60 mi (7,832.03 km) |
| Sioux City to Codroipo | 4,947.08 mi (7,961.56 km) |
| Sioux City to Cogoleto | 4,862.42 mi (7,825.31 km) |
| Sioux City to Colle di Val d'Elsa | 5,000.36 mi (8,047.30 km) |
| Sioux City to Colle Salvetti | 4,966.96 mi (7,993.55 km) |
| Sioux City to Collecchio | 4,904.10 mi (7,892.39 km) |
| Sioux City to Colleferro | 5,149.03 mi (8,286.56 km) |
