| Douarnenez to Olympia Heights (Florida) | 4,288.11 mi (6,901.05 km) |
| Douarnenez to Omaha (Nebraska) | 4,255.67 mi (6,848.84 km) |
| Douarnenez to On Top of the World Designated Place (Florida) | 4,219.36 mi (6,790.41 km) |
| Douarnenez to Onalaska (Wisconsin) | 3,950.02 mi (6,356.94 km) |
| Douarnenez to Oneida (New York) | 3,341.33 mi (5,377.35 km) |
| Douarnenez to Oneonta (New York) | 3,338.73 mi (5,373.17 km) |
| Douarnenez to Ontario (California) | 5,429.88 mi (8,738.54 km) |
| Douarnenez to Ontario (Oregon) | 4,877.38 mi (7,849.39 km) |
| Douarnenez to Opa-locka (Florida) | 4,276.05 mi (6,881.63 km) |
| Douarnenez to Opelika (Alabama) | 4,195.03 mi (6,751.25 km) |
| Douarnenez to Opelousas (Louisiana) | 4,586.81 mi (7,381.75 km) |
| Douarnenez to Orange (California) | 5,450.30 mi (8,771.41 km) |
| Douarnenez to Orange (Texas) | 4,678.58 mi (7,529.44 km) |
| Douarnenez to Orange City (Florida) | 4,182.16 mi (6,730.54 km) |
| Douarnenez to Orangeburg (South Carolina) | 3,958.43 mi (6,370.47 km) |
