| Idar-Oberstein to Carson (California) | 5,772.79 mi (9,290.40 km) |
| Idar-Oberstein to Carson City (Nevada) | 5,504.34 mi (8,858.39 km) |
| Idar-Oberstein to Carteret (New Jersey) | 3,824.65 mi (6,155.19 km) |
| Idar-Oberstein to Cartersville (Georgia) | 4,551.96 mi (7,325.68 km) |
| Idar-Oberstein to Carthage (Missouri) | 4,774.47 mi (7,683.77 km) |
| Idar-Oberstein to Cary (Illinois) | 4,298.93 mi (6,918.46 km) |
| Idar-Oberstein to Cary (North Carolina) | 4,230.15 mi (6,807.77 km) |
| Idar-Oberstein to Casa de Oro-Mount Helix (California) | 5,795.88 mi (9,327.56 km) |
| Idar-Oberstein to Casa Grande (Arizona) | 5,619.99 mi (9,044.49 km) |
| Idar-Oberstein to Casas Adobes (Arizona) | 5,626.87 mi (9,055.57 km) |
| Idar-Oberstein to Cascades (Virginia) | 4,021.45 mi (6,471.90 km) |
| Idar-Oberstein to Casper (Wyoming) | 4,892.88 mi (7,874.34 km) |
| Idar-Oberstein to Casselberry (Florida) | 4,677.89 mi (7,528.34 km) |
| Idar-Oberstein to Castaic (California) | 5,746.33 mi (9,247.83 km) |
| Idar-Oberstein to Castle Pines (Colorado) | 5,027.48 mi (8,090.94 km) |
