| Difficult Run to Cognac | 3,810.05 mi (6,131.68 km) |
| Difficult Run to Cogolin | 4,187.70 mi (6,739.45 km) |
| Difficult Run to Colmar | 4,075.38 mi (6,558.69 km) |
| Difficult Run to Colombes | 3,838.02 mi (6,176.70 km) |
| Difficult Run to Colomiers | 3,942.56 mi (6,344.93 km) |
| Difficult Run to Combs-la-Ville | 3,857.58 mi (6,208.17 km) |
| Difficult Run to Comines | 3,822.87 mi (6,152.32 km) |
| Difficult Run to Compiegne | 3,849.33 mi (6,194.89 km) |
| Difficult Run to Concarneau | 3,597.94 mi (5,790.32 km) |
| Difficult Run to Conde-sur-l'Escaut | 3,854.53 mi (6,203.27 km) |
| Difficult Run to Conflans-Sainte-Honorine | 3,829.60 mi (6,163.15 km) |
| Difficult Run to Corbas | 4,041.74 mi (6,504.55 km) |
| Difficult Run to Corbeil-Essonnes | 3,855.74 mi (6,205.22 km) |
| Difficult Run to Cormeilles-en-Parisis | 3,834.59 mi (6,171.18 km) |
| Difficult Run to Cosne sur Loire | 3,906.68 mi (6,287.20 km) |
