| Potomac to Castle Pines (Colorado) | 1,475.56 mi (2,374.68 km) |
| Potomac to Castle Rock (Colorado) | 1,475.46 mi (2,374.52 km) |
| Potomac to Castro Valley (California) | 2,407.58 mi (3,874.63 km) |
| Potomac to Catalina Foothills (Arizona) | 1,935.37 mi (3,114.68 km) |
| Potomac to Cataño (Puerto Rico) | 1,568.43 mi (2,524.15 km) |
| Potomac to Cathedral City (California) | 2,195.07 mi (3,532.62 km) |
| Potomac to Catonsville (Maryland) | 29.77 mi (47.90 km) |
| Potomac to Cave Spring (Virginia) | 196.58 mi (316.37 km) |
| Potomac to Cayce (South Carolina) | 410.19 mi (660.14 km) |
| Potomac to Cayey (Puerto Rico) | 1,588.54 mi (2,556.50 km) |
| Potomac to Cedar City (Utah) | 1,934.89 mi (3,113.91 km) |
| Potomac to Cedar Falls (Iowa) | 833.08 mi (1,340.72 km) |
| Potomac to Cedar Hill (Texas) | 1,190.35 mi (1,915.68 km) |
| Potomac to Cedar Lake (Indiana) | 564.27 mi (908.10 km) |
| Potomac to Cedar Mill (Oregon) | 2,342.16 mi (3,769.35 km) |
