| Helena to Carlsbad (California) | 971.19 mi (1,562.98 km) |
| Helena to Carlsbad (New Mexico) | 1,063.63 mi (1,711.75 km) |
| Helena to Carmel (Indiana) | 1,372.31 mi (2,208.51 km) |
| Helena to Carmichael (California) | 724.74 mi (1,166.36 km) |
| Helena to Carney (Maryland) | 1,844.02 mi (2,967.66 km) |
| Helena to Carnot-Moon (Pennsylvania) | 1,634.60 mi (2,630.63 km) |
| Helena to Carol Stream (Illinois) | 1,220.30 mi (1,963.89 km) |
| Helena to Carolina (Puerto Rico) | 3,247.57 mi (5,226.46 km) |
| Helena to Carolina Forest (South Carolina) | 1,940.16 mi (3,122.39 km) |
| Helena to Carpentersville (Illinois) | 1,207.24 mi (1,942.86 km) |
| Helena to Carpinteria (California) | 929.28 mi (1,495.53 km) |
| Helena to Carrboro (North Carolina) | 1,845.44 mi (2,969.95 km) |
| Helena to Carroll (Iowa) | 901.45 mi (1,450.74 km) |
| Helena to Carrollton (Georgia) | 1,671.21 mi (2,689.56 km) |
| Helena to Carrollton (Texas) | 1,231.83 mi (1,982.44 km) |
