| Hard to Clarkston (Georgia) | 4,710.68 mi (7,581.11 km) |
| Hard to Clarksville (Indiana) | 4,560.43 mi (7,339.30 km) |
| Hard to Clarksville (Tennessee) | 4,706.24 mi (7,573.97 km) |
| Hard to Clawson (Michigan) | 4,264.86 mi (6,863.64 km) |
| Hard to Clay (Alabama) | 4,814.40 mi (7,748.03 km) |
| Hard to Clayton (California) | 5,824.74 mi (9,374.02 km) |
| Hard to Clayton (Missouri) | 4,724.35 mi (7,603.10 km) |
| Hard to Clayton (North Carolina) | 4,381.44 mi (7,051.24 km) |
| Hard to Clayton (Ohio) | 4,431.59 mi (7,131.95 km) |
| Hard to Clearfield (Utah) | 5,352.67 mi (8,614.29 km) |
| Hard to Clearlake (California) | 5,783.22 mi (9,307.20 km) |
| Hard to Clearwater (Florida) | 4,927.67 mi (7,930.31 km) |
| Hard to Cleburne (Texas) | 5,313.38 mi (8,551.06 km) |
| Hard to Clemmons (North Carolina) | 4,446.07 mi (7,155.26 km) |
| Hard to Clemson (South Carolina) | 4,609.96 mi (7,419.02 km) |
