| Difficult Run to Casamassima | 4,727.02 mi (7,607.40 km) |
| Difficult Run to Casandrino | 4,610.63 mi (7,420.09 km) |
| Difficult Run to Casapulla | 4,607.20 mi (7,414.57 km) |
| Difficult Run to Casarano | 4,817.50 mi (7,753.02 km) |
| Difficult Run to Casatenovo | 4,231.42 mi (6,809.81 km) |
| Difficult Run to Casciana Terme | 4,359.40 mi (7,015.77 km) |
| Difficult Run to Cascina | 4,351.14 mi (7,002.48 km) |
| Difficult Run to Caselle Torinese | 4,176.16 mi (6,720.88 km) |
| Difficult Run to Caserta | 4,609.41 mi (7,418.12 km) |
| Difficult Run to Casier | 4,359.89 mi (7,016.56 km) |
| Difficult Run to Casorate Primo | 4,230.98 mi (6,809.11 km) |
| Difficult Run to Casoria | 4,614.06 mi (7,425.62 km) |
| Difficult Run to Cassano al Ionio | 4,745.13 mi (7,636.55 km) |
| Difficult Run to Cassano d'Adda | 4,245.49 mi (6,832.45 km) |
| Difficult Run to Cassano delle Murge | 4,723.02 mi (7,600.96 km) |
