| Mangalia to Olympia Heights (Florida) | 5,862.75 mi (9,435.18 km) |
| Mangalia to Omaha (Nebraska) | 5,628.94 mi (9,058.90 km) |
| Mangalia to On Top of the World Designated Place (Florida) | 5,773.31 mi (9,291.25 km) |
| Mangalia to Onalaska (Wisconsin) | 5,333.70 mi (8,583.76 km) |
| Mangalia to Oneida (New York) | 4,831.66 mi (7,775.80 km) |
| Mangalia to Oneonta (New York) | 4,837.78 mi (7,785.66 km) |
| Mangalia to Ontario (California) | 6,651.72 mi (10,704.91 km) |
| Mangalia to Ontario (Oregon) | 6,007.26 mi (9,667.75 km) |
| Mangalia to Opa-locka (Florida) | 5,850.34 mi (9,415.22 km) |
| Mangalia to Opelika (Alabama) | 5,714.43 mi (9,196.49 km) |
| Mangalia to Opelousas (Louisiana) | 6,081.14 mi (9,786.64 km) |
| Mangalia to Orange (California) | 6,671.59 mi (10,736.88 km) |
| Mangalia to Orange (Texas) | 6,164.69 mi (9,921.10 km) |
| Mangalia to Orange City (Florida) | 5,740.88 mi (9,239.05 km) |
| Mangalia to Orangeburg (South Carolina) | 5,495.09 mi (8,843.49 km) |
