| Keystone to Cibolo (Texas) | 949.25 mi (1,527.66 km) |
| Keystone to Cicero (Illinois) | 990.97 mi (1,594.81 km) |
| Keystone to Cimarron Hills (Colorado) | 1,467.56 mi (2,361.81 km) |
| Keystone to Cincinnati (Ohio) | 768.53 mi (1,236.83 km) |
| Keystone to Cinco Ranch (Texas) | 803.07 mi (1,292.42 km) |
| Keystone to Circleville (Ohio) | 793.08 mi (1,276.34 km) |
| Keystone to Citrus (California) | 2,116.99 mi (3,406.96 km) |
| Keystone to Citrus Heights (California) | 2,328.02 mi (3,746.58 km) |
| Keystone to Citrus Park (Florida) | 4.61 mi (7.42 km) |
| Keystone to Claiborne (Louisiana) | 647.92 mi (1,042.72 km) |
| Keystone to Claremont (California) | 2,107.07 mi (3,391.00 km) |
| Keystone to Claremont (New Hampshire) | 1,198.22 mi (1,928.36 km) |
| Keystone to Claremore (Oklahoma) | 946.09 mi (1,522.58 km) |
| Keystone to Clarksburg (Maryland) | 825.13 mi (1,327.92 km) |
| Keystone to Clarksburg (West Virginia) | 781.68 mi (1,258.00 km) |
