| Helena to Cadillac (Michigan) | 1,294.03 mi (2,082.55 km) |
| Helena to Caguas (Puerto Rico) | 3,253.77 mi (5,236.44 km) |
| Helena to Cahokia (Illinois) | 1,236.36 mi (1,989.72 km) |
| Helena to Calabasas (California) | 928.41 mi (1,494.13 km) |
| Helena to Caldwell (Idaho) | 304.42 mi (489.92 km) |
| Helena to Caledonia (Wisconsin) | 1,209.38 mi (1,946.31 km) |
| Helena to Calera (Alabama) | 1,620.34 mi (2,607.69 km) |
| Helena to Calexico (California) | 978.55 mi (1,574.82 km) |
| Helena to Calhoun (Georgia) | 1,637.45 mi (2,635.23 km) |
| Helena to California (Maryland) | 1,881.67 mi (3,028.26 km) |
| Helena to California City (California) | 846.79 mi (1,362.77 km) |
| Helena to Callaway (Florida) | 1,814.86 mi (2,920.74 km) |
| Helena to Calumet City (Illinois) | 1,256.16 mi (2,021.60 km) |
| Helena to Calverton (Maryland) | 1,834.99 mi (2,953.14 km) |
| Helena to Camano (Washington) | 500.59 mi (805.63 km) |
