| Keystone to Conyers (Georgia) | 391.17 mi (629.53 km) |
| Keystone to Cookeville (Tennessee) | 579.42 mi (932.49 km) |
| Keystone to Coolidge (Arizona) | 1,747.40 mi (2,812.17 km) |
| Keystone to Coon Rapids (Minnesota) | 1,316.03 mi (2,117.95 km) |
| Keystone to Cooper City (Florida) | 202.49 mi (325.88 km) |
| Keystone to Coos Bay (Oregon) | 2,528.28 mi (4,068.87 km) |
| Keystone to Copiague (New York) | 1,011.60 mi (1,628.02 km) |
| Keystone to Coppell (Texas) | 918.05 mi (1,477.46 km) |
| Keystone to Copperas Cove (Texas) | 941.81 mi (1,515.70 km) |
| Keystone to Coral Gables (Florida) | 220.69 mi (355.16 km) |
| Keystone to Coral Springs (Florida) | 192.93 mi (310.49 km) |
| Keystone to Coral Terrace (Florida) | 217.09 mi (349.37 km) |
| Keystone to Coralville (Iowa) | 1,065.57 mi (1,714.88 km) |
| Keystone to Coram (New York) | 1,035.01 mi (1,665.68 km) |
| Keystone to Corcoran (California) | 2,217.60 mi (3,568.89 km) |
