| Romeoville to Castle Pines (Colorado) | 891.69 mi (1,435.04 km) |
| Romeoville to Castle Rock (Colorado) | 892.38 mi (1,436.14 km) |
| Romeoville to Castro Valley (California) | 1,814.54 mi (2,920.22 km) |
| Romeoville to Catalina Foothills (Arizona) | 1,407.20 mi (2,264.67 km) |
| Romeoville to Cataño (Puerto Rico) | 2,059.12 mi (3,313.83 km) |
| Romeoville to Cathedral City (California) | 1,631.99 mi (2,626.44 km) |
| Romeoville to Catonsville (Maryland) | 618.63 mi (995.58 km) |
| Romeoville to Cave Spring (Virginia) | 528.03 mi (849.78 km) |
| Romeoville to Cayce (South Carolina) | 655.58 mi (1,055.05 km) |
| Romeoville to Cayey (Puerto Rico) | 2,076.88 mi (3,342.42 km) |
| Romeoville to Cedar City (Utah) | 1,352.26 mi (2,176.26 km) |
| Romeoville to Cedar Falls (Iowa) | 231.53 mi (372.61 km) |
| Romeoville to Cedar Hill (Texas) | 792.38 mi (1,275.21 km) |
| Romeoville to Cedar Lake (Indiana) | 38.70 mi (62.28 km) |
| Romeoville to Cedar Mill (Oregon) | 1,743.64 mi (2,806.12 km) |
