| Harpenden to Castle Rock (Colorado) | 4,679.46 mi (7,530.86 km) |
| Harpenden to Castro Valley (California) | 5,325.16 mi (8,570.01 km) |
| Harpenden to Catalina Foothills (Arizona) | 5,271.85 mi (8,484.22 km) |
| Harpenden to Cataño (Puerto Rico) | 4,195.36 mi (6,751.78 km) |
| Harpenden to Cathedral City (California) | 5,373.96 mi (8,648.55 km) |
| Harpenden to Catonsville (Maryland) | 3,620.66 mi (5,826.88 km) |
| Harpenden to Cave Spring (Virginia) | 3,846.64 mi (6,190.57 km) |
| Harpenden to Cayce (South Carolina) | 4,044.77 mi (6,509.44 km) |
| Harpenden to Cayey (Puerto Rico) | 4,213.18 mi (6,780.46 km) |
| Harpenden to Cedar City (Utah) | 5,047.94 mi (8,123.87 km) |
| Harpenden to Cedar Falls (Iowa) | 4,078.82 mi (6,564.23 km) |
| Harpenden to Cedar Hill (Texas) | 4,746.29 mi (7,638.42 km) |
| Harpenden to Cedar Lake (Indiana) | 3,945.63 mi (6,349.88 km) |
| Harpenden to Cedar Mill (Oregon) | 4,892.65 mi (7,873.96 km) |
| Harpenden to Cedar Park (Texas) | 4,887.65 mi (7,865.91 km) |
