| Merthyr Tudful to Cloverly (Maryland) | 3,516.29 mi (5,658.92 km) |
| Merthyr Tudful to Clovis (California) | 5,213.82 mi (8,390.83 km) |
| Merthyr Tudful to Clovis (New Mexico) | 4,773.18 mi (7,681.69 km) |
| Merthyr Tudful to Clute (Texas) | 4,752.37 mi (7,648.19 km) |
| Merthyr Tudful to Coachella (California) | 5,274.33 mi (8,488.21 km) |
| Merthyr Tudful to Coalinga (California) | 5,273.05 mi (8,486.16 km) |
| Merthyr Tudful to Coamo (Puerto Rico) | 4,095.07 mi (6,590.39 km) |
| Merthyr Tudful to Coatesville (Pennsylvania) | 3,429.17 mi (5,518.72 km) |
| Merthyr Tudful to Cockeysville (Maryland) | 3,484.53 mi (5,607.81 km) |
| Merthyr Tudful to Cocoa (Florida) | 4,181.18 mi (6,728.96 km) |
| Merthyr Tudful to Cocoa Beach (Florida) | 4,177.72 mi (6,723.39 km) |
| Merthyr Tudful to Coconut Creek (Florida) | 4,261.68 mi (6,858.50 km) |
| Merthyr Tudful to Coeur d'Alene (Idaho) | 4,523.26 mi (7,279.48 km) |
| Merthyr Tudful to Cohoes (New York) | 3,224.32 mi (5,189.03 km) |
| Merthyr Tudful to Cold Springs (Nevada) | 5,061.17 mi (8,145.16 km) |
