| Harpenden to Castelfidardo | 864.41 mi (1,391.13 km) |
| Harpenden to Castelfiorentino | 772.41 mi (1,243.08 km) |
| Harpenden to Castelfranco di Sopra | 789.94 mi (1,271.29 km) |
| Harpenden to Castelfranco di Sotto | 760.25 mi (1,223.51 km) |
| Harpenden to Castelfranco Emilia | 722.82 mi (1,163.27 km) |
| Harpenden to Castelfranco Veneto | 701.29 mi (1,128.62 km) |
| Harpenden to Castellabate | 1,079.31 mi (1,736.97 km) |
| Harpenden to Castellammare del Golfo | 1,148.07 mi (1,847.64 km) |
| Harpenden to Castellammare di Stabia | 1,041.40 mi (1,675.98 km) |
| Harpenden to Castellamonte | 576.78 mi (928.24 km) |
| Harpenden to Castellana Grotte | 1,121.10 mi (1,804.23 km) |
| Harpenden to Castellaneta | 1,126.00 mi (1,812.13 km) |
| Harpenden to Castellanza | 600.32 mi (966.13 km) |
| Harpenden to Castellarano | 715.49 mi (1,151.48 km) |
| Harpenden to Castelleone | 644.60 mi (1,037.39 km) |
