| Difficult Run to Cortona | 4,427.73 mi (7,125.75 km) |
| Difficult Run to Cosenza | 4,760.64 mi (7,661.51 km) |
| Difficult Run to Cossato | 4,186.45 mi (6,737.43 km) |
| Difficult Run to Costa Volpino | 4,260.74 mi (6,857.00 km) |
| Difficult Run to Creazzo | 4,329.28 mi (6,967.30 km) |
| Difficult Run to Crema | 4,258.01 mi (6,852.60 km) |
| Difficult Run to Cremona | 4,280.62 mi (6,889.00 km) |
| Difficult Run to Crevalcore | 4,342.36 mi (6,988.36 km) |
| Difficult Run to Crispiano | 4,754.19 mi (7,651.13 km) |
| Difficult Run to Crosia | 4,773.35 mi (7,681.96 km) |
| Difficult Run to Crotone | 4,807.52 mi (7,736.95 km) |
| Difficult Run to Cuneo | 4,196.99 mi (6,754.40 km) |
| Difficult Run to Cuorgne | 4,169.67 mi (6,710.43 km) |
| Difficult Run to Cusano Milanino | 4,230.67 mi (6,808.60 km) |
| Difficult Run to Cutro | 4,803.51 mi (7,730.51 km) |
