| Gretna to Castle Pines (Colorado) | 1,067.32 mi (1,717.68 km) |
| Gretna to Castle Rock (Colorado) | 1,063.26 mi (1,711.16 km) |
| Gretna to Castro Valley (California) | 1,904.63 mi (3,065.20 km) |
| Gretna to Catalina Foothills (Arizona) | 1,241.45 mi (1,997.92 km) |
| Gretna to Cataño (Puerto Rico) | 1,697.51 mi (2,731.87 km) |
| Gretna to Cathedral City (California) | 1,568.86 mi (2,524.84 km) |
| Gretna to Catonsville (Maryland) | 993.45 mi (1,598.80 km) |
| Gretna to Cave Spring (Virginia) | 767.16 mi (1,234.62 km) |
| Gretna to Cayce (South Carolina) | 597.00 mi (960.78 km) |
| Gretna to Cayey (Puerto Rico) | 1,708.48 mi (2,749.53 km) |
| Gretna to Cedar City (Utah) | 1,423.19 mi (2,290.40 km) |
| Gretna to Cedar Falls (Iowa) | 881.35 mi (1,418.39 km) |
| Gretna to Cedar Hill (Texas) | 447.70 mi (720.50 km) |
| Gretna to Cedar Lake (Indiana) | 805.14 mi (1,295.74 km) |
| Gretna to Cedar Mill (Oregon) | 2,068.79 mi (3,329.39 km) |
