| Rock Island to Commerce (California) | 1,584.47 mi (2,549.95 km) |
| Rock Island to Commerce City (Colorado) | 754.65 mi (1,214.50 km) |
| Rock Island to Compton (California) | 1,591.58 mi (2,561.40 km) |
| Rock Island to Comstock Park (Michigan) | 273.33 mi (439.88 km) |
| Rock Island to Concord (California) | 1,677.74 mi (2,700.06 km) |
| Rock Island to Concord (Missouri) | 204.74 mi (329.50 km) |
| Rock Island to Concord (New Hampshire) | 976.81 mi (1,572.03 km) |
| Rock Island to Concord (North Carolina) | 681.90 mi (1,097.41 km) |
| Rock Island to Conneaut (Ohio) | 517.29 mi (832.50 km) |
| Rock Island to Connersville (Indiana) | 311.78 mi (501.76 km) |
| Rock Island to Conroe (Texas) | 817.11 mi (1,315.01 km) |
| Rock Island to Converse (Texas) | 932.75 mi (1,501.12 km) |
| Rock Island to Conway (Arkansas) | 453.48 mi (729.81 km) |
| Rock Island to Conway (Florida) | 1,036.64 mi (1,668.30 km) |
| Rock Island to Conway (South Carolina) | 821.11 mi (1,321.44 km) |
