| Southborough to Castelfidardo | 816.22 mi (1,313.59 km) |
| Southborough to Castelfiorentino | 722.12 mi (1,162.14 km) |
| Southborough to Castelfranco di Sopra | 740.16 mi (1,191.18 km) |
| Southborough to Castelfranco di Sotto | 709.87 mi (1,142.43 km) |
| Southborough to Castelfranco Emilia | 673.69 mi (1,084.20 km) |
| Southborough to Castelfranco Veneto | 654.81 mi (1,053.82 km) |
| Southborough to Castellabate | 1,029.32 mi (1,656.53 km) |
| Southborough to Castellammare del Golfo | 1,096.04 mi (1,763.91 km) |
| Southborough to Castellammare di Stabia | 991.39 mi (1,595.48 km) |
| Southborough to Castellamonte | 525.44 mi (845.62 km) |
| Southborough to Castellana Grotte | 1,073.21 mi (1,727.16 km) |
| Southborough to Castellaneta | 1,077.71 mi (1,734.40 km) |
| Southborough to Castellanza | 550.36 mi (885.72 km) |
| Southborough to Castellarano | 666.07 mi (1,071.93 km) |
| Southborough to Castelleone | 595.10 mi (957.73 km) |
