| Rock Island to Cordele (Georgia) | 757.33 mi (1,218.81 km) |
| Rock Island to Corinth (Mississippi) | 464.40 mi (747.38 km) |
| Rock Island to Corinth (Texas) | 676.28 mi (1,088.36 km) |
| Rock Island to Cornelius (North Carolina) | 667.94 mi (1,074.94 km) |
| Rock Island to Cornelius (Oregon) | 1,639.72 mi (2,638.88 km) |
| Rock Island to Corning (New York) | 697.46 mi (1,122.46 km) |
| Rock Island to Corona (California) | 1,558.86 mi (2,508.74 km) |
| Rock Island to Coronado (California) | 1,578.44 mi (2,540.26 km) |
| Rock Island to Corpus Christi (Texas) | 1,024.38 mi (1,648.58 km) |
| Rock Island to Corsicana (Texas) | 725.30 mi (1,167.26 km) |
| Rock Island to Cortland (New York) | 742.40 mi (1,194.78 km) |
| Rock Island to Corvallis (Oregon) | 1,654.21 mi (2,662.19 km) |
| Rock Island to Coshocton (Ohio) | 463.76 mi (746.34 km) |
| Rock Island to Costa Mesa (California) | 1,582.85 mi (2,547.35 km) |
| Rock Island to Coto de Caza (California) | 1,568.52 mi (2,524.29 km) |
