| Huercal-Overa to Olympia Heights (Florida) | 4,557.30 mi (7,334.27 km) |
| Huercal-Overa to Omaha (Nebraska) | 4,771.07 mi (7,678.30 km) |
| Huercal-Overa to On Top of the World Designated Place (Florida) | 4,538.77 mi (7,304.44 km) |
| Huercal-Overa to Onalaska (Wisconsin) | 4,466.83 mi (7,188.66 km) |
| Huercal-Overa to Oneida (New York) | 3,782.18 mi (6,086.83 km) |
| Huercal-Overa to Oneonta (New York) | 3,769.35 mi (6,066.18 km) |
| Huercal-Overa to Ontario (California) | 6,002.16 mi (9,659.54 km) |
| Huercal-Overa to Ontario (Oregon) | 5,501.46 mi (8,853.74 km) |
| Huercal-Overa to Opa-locka (Florida) | 4,546.52 mi (7,316.92 km) |
| Huercal-Overa to Opelika (Alabama) | 4,571.84 mi (7,357.67 km) |
| Huercal-Overa to Opelousas (Louisiana) | 4,984.74 mi (8,022.17 km) |
| Huercal-Overa to Orange (California) | 6,022.36 mi (9,692.05 km) |
| Huercal-Overa to Orange (Texas) | 5,083.46 mi (8,181.03 km) |
| Huercal-Overa to Orange City (Florida) | 4,492.87 mi (7,230.58 km) |
| Huercal-Overa to Orangeburg (South Carolina) | 4,316.17 mi (6,946.20 km) |
