| Harpenden to Cookeville (Tennessee) | 4,119.04 mi (6,628.95 km) |
| Harpenden to Coolidge (Arizona) | 5,258.97 mi (8,463.49 km) |
| Harpenden to Coon Rapids (Minnesota) | 3,983.47 mi (6,410.78 km) |
| Harpenden to Cooper City (Florida) | 4,404.98 mi (7,089.13 km) |
| Harpenden to Coos Bay (Oregon) | 5,056.10 mi (8,137.00 km) |
| Harpenden to Copiague (New York) | 3,422.22 mi (5,507.53 km) |
| Harpenden to Coppell (Texas) | 4,727.61 mi (7,608.35 km) |
| Harpenden to Copperas Cove (Texas) | 4,859.32 mi (7,820.32 km) |
| Harpenden to Coral Gables (Florida) | 4,421.76 mi (7,116.14 km) |
| Harpenden to Coral Springs (Florida) | 4,392.49 mi (7,069.02 km) |
| Harpenden to Coral Terrace (Florida) | 4,421.00 mi (7,114.92 km) |
| Harpenden to Coralville (Iowa) | 4,086.52 mi (6,576.62 km) |
| Harpenden to Coram (New York) | 3,397.36 mi (5,467.52 km) |
| Harpenden to Corcoran (California) | 5,343.66 mi (8,599.79 km) |
| Harpenden to Cordele (Georgia) | 4,253.73 mi (6,845.72 km) |
