| Southborough to Cookeville (Tennessee) | 4,160.42 mi (6,695.56 km) |
| Southborough to Coolidge (Arizona) | 5,307.38 mi (8,541.40 km) |
| Southborough to Coon Rapids (Minnesota) | 4,030.87 mi (6,487.06 km) |
| Southborough to Cooper City (Florida) | 4,438.96 mi (7,143.81 km) |
| Southborough to Coos Bay (Oregon) | 5,108.16 mi (8,220.79 km) |
| Southborough to Copiague (New York) | 3,461.51 mi (5,570.77 km) |
| Southborough to Coppell (Texas) | 4,771.74 mi (7,679.38 km) |
| Southborough to Copperas Cove (Texas) | 4,903.12 mi (7,890.81 km) |
| Southborough to Coral Gables (Florida) | 4,455.55 mi (7,170.51 km) |
| Southborough to Coral Springs (Florida) | 4,426.57 mi (7,123.87 km) |
| Southborough to Coral Terrace (Florida) | 4,454.83 mi (7,169.35 km) |
| Southborough to Coralville (Iowa) | 4,132.23 mi (6,650.18 km) |
| Southborough to Coram (New York) | 3,436.64 mi (5,530.73 km) |
| Southborough to Corcoran (California) | 5,394.33 mi (8,681.34 km) |
| Southborough to Cordele (Georgia) | 4,292.40 mi (6,907.94 km) |
