| Oliveira de Frades to Olympia Heights (Florida) | 4,180.38 mi (6,727.67 km) |
| Oliveira de Frades to Omaha (Nebraska) | 4,364.41 mi (7,023.84 km) |
| Oliveira de Frades to On Top of the World Designated Place (Florida) | 4,151.58 mi (6,681.31 km) |
| Oliveira de Frades to Onalaska (Wisconsin) | 4,060.20 mi (6,534.25 km) |
| Oliveira de Frades to Oneida (New York) | 3,377.62 mi (5,435.75 km) |
| Oliveira de Frades to Oneonta (New York) | 3,365.51 mi (5,416.27 km) |
| Oliveira de Frades to Ontario (California) | 5,597.17 mi (9,007.77 km) |
| Oliveira de Frades to Ontario (Oregon) | 5,104.04 mi (8,214.17 km) |
| Oliveira de Frades to Opa-locka (Florida) | 4,169.28 mi (6,709.80 km) |
| Oliveira de Frades to Opelika (Alabama) | 4,175.36 mi (6,719.59 km) |
| Oliveira de Frades to Opelousas (Louisiana) | 4,586.18 mi (7,380.74 km) |
| Oliveira de Frades to Orange (California) | 5,617.34 mi (9,040.23 km) |
| Oliveira de Frades to Orange (Texas) | 4,684.18 mi (7,538.46 km) |
| Oliveira de Frades to Orange City (Florida) | 4,107.18 mi (6,609.87 km) |
| Oliveira de Frades to Orangeburg (South Carolina) | 3,921.91 mi (6,311.71 km) |
