| Boppard to Olympia Heights (Florida) | 4,784.10 mi (7,699.27 km) |
| Boppard to Omaha (Nebraska) | 4,617.34 mi (7,430.89 km) |
| Boppard to On Top of the World Designated Place (Florida) | 4,696.33 mi (7,558.02 km) |
| Boppard to Onalaska (Wisconsin) | 4,315.68 mi (6,945.41 km) |
| Boppard to Oneida (New York) | 3,769.70 mi (6,066.74 km) |
| Boppard to Oneonta (New York) | 3,773.10 mi (6,072.22 km) |
| Boppard to Ontario (California) | 5,723.38 mi (9,210.89 km) |
| Boppard to Ontario (Oregon) | 5,122.83 mi (8,244.40 km) |
| Boppard to Opa-locka (Florida) | 4,771.68 mi (7,679.28 km) |
| Boppard to Opelika (Alabama) | 4,645.60 mi (7,476.36 km) |
| Boppard to Opelousas (Louisiana) | 5,021.23 mi (8,080.89 km) |
| Boppard to Orange (California) | 5,743.72 mi (9,243.62 km) |
| Boppard to Orange (Texas) | 5,107.97 mi (8,220.48 km) |
| Boppard to Orange City (Florida) | 4,663.17 mi (7,504.65 km) |
| Boppard to Orangeburg (South Carolina) | 4,421.34 mi (7,115.47 km) |
