| Rock Island to Clemson (South Carolina) | 630.68 mi (1,014.98 km) |
| Rock Island to Clermont (Florida) | 1,023.61 mi (1,647.34 km) |
| Rock Island to Cleveland (Mississippi) | 533.87 mi (859.18 km) |
| Rock Island to Cleveland (Ohio) | 460.66 mi (741.36 km) |
| Rock Island to Cleveland (Tennessee) | 533.21 mi (858.13 km) |
| Rock Island to Cleveland Heights (Ohio) | 466.58 mi (750.89 km) |
| Rock Island to Cliffside Park (New Jersey) | 863.26 mi (1,389.28 km) |
| Rock Island to Clifton (Colorado) | 955.05 mi (1,537.01 km) |
| Rock Island to Clifton (New Jersey) | 854.08 mi (1,374.50 km) |
| Rock Island to Clinton (Iowa) | 31.26 mi (50.31 km) |
| Rock Island to Clinton (Maryland) | 745.84 mi (1,200.32 km) |
| Rock Island to Clinton (Mississippi) | 629.99 mi (1,013.87 km) |
| Rock Island to Clinton (Utah) | 1,112.40 mi (1,790.24 km) |
| Rock Island to Clive (Iowa) | 166.57 mi (268.06 km) |
| Rock Island to Cloquet (Minnesota) | 375.03 mi (603.55 km) |
