| Rock Island to Conyers (Georgia) | 648.33 mi (1,043.38 km) |
| Rock Island to Cookeville (Tennessee) | 457.81 mi (736.77 km) |
| Rock Island to Coolidge (Arizona) | 1,289.89 mi (2,075.88 km) |
| Rock Island to Coon Rapids (Minnesota) | 290.37 mi (467.30 km) |
| Rock Island to Cooper City (Florida) | 1,216.64 mi (1,958.00 km) |
| Rock Island to Coos Bay (Oregon) | 1,709.65 mi (2,751.41 km) |
| Rock Island to Copiague (New York) | 895.67 mi (1,441.44 km) |
| Rock Island to Coppell (Texas) | 684.86 mi (1,102.17 km) |
| Rock Island to Copperas Cove (Texas) | 822.72 mi (1,324.04 km) |
| Rock Island to Coral Gables (Florida) | 1,238.31 mi (1,992.87 km) |
| Rock Island to Coral Springs (Florida) | 1,203.54 mi (1,936.92 km) |
| Rock Island to Coral Terrace (Florida) | 1,234.75 mi (1,987.14 km) |
| Rock Island to Coralville (Iowa) | 54.74 mi (88.10 km) |
| Rock Island to Coram (New York) | 913.44 mi (1,470.03 km) |
| Rock Island to Corcoran (California) | 1,596.57 mi (2,569.43 km) |
