| Hard to Cloverly (Maryland) | 4,167.29 mi (6,706.61 km) |
| Hard to Clovis (California) | 5,826.87 mi (9,377.45 km) |
| Hard to Clovis (New Mexico) | 5,420.61 mi (8,723.63 km) |
| Hard to Clute (Texas) | 5,405.63 mi (8,699.53 km) |
| Hard to Coachella (California) | 5,902.34 mi (9,498.89 km) |
| Hard to Coalinga (California) | 5,885.88 mi (9,472.41 km) |
| Hard to Coamo (Puerto Rico) | 4,660.09 mi (7,499.70 km) |
| Hard to Coatesville (Pennsylvania) | 4,080.31 mi (6,566.62 km) |
| Hard to Cockeysville (Maryland) | 4,135.66 mi (6,655.71 km) |
| Hard to Cocoa (Florida) | 4,821.20 mi (7,758.98 km) |
| Hard to Cocoa Beach (Florida) | 4,817.43 mi (7,752.91 km) |
| Hard to Coconut Creek (Florida) | 4,896.64 mi (7,880.38 km) |
| Hard to Coeur d'Alene (Idaho) | 5,116.07 mi (8,233.52 km) |
| Hard to Cohoes (New York) | 3,876.69 mi (6,238.94 km) |
| Hard to Cold Springs (Nevada) | 5,666.79 mi (9,119.82 km) |
