| Vila Nova de Gaia to Olympia Heights (Florida) | 4,153.26 mi (6,684.03 km) |
| Vila Nova de Gaia to Omaha (Nebraska) | 4,329.87 mi (6,968.25 km) |
| Vila Nova de Gaia to On Top of the World Designated Place (Florida) | 4,122.67 mi (6,634.80 km) |
| Vila Nova de Gaia to Onalaska (Wisconsin) | 4,025.54 mi (6,478.48 km) |
| Vila Nova de Gaia to Oneida (New York) | 3,344.61 mi (5,382.64 km) |
| Vila Nova de Gaia to Oneonta (New York) | 3,332.79 mi (5,363.61 km) |
| Vila Nova de Gaia to Ontario (California) | 5,561.69 mi (8,950.67 km) |
| Vila Nova de Gaia to Ontario (Oregon) | 5,067.71 mi (8,155.70 km) |
| Vila Nova de Gaia to Opa-locka (Florida) | 4,142.11 mi (6,666.09 km) |
| Vila Nova de Gaia to Opelika (Alabama) | 4,144.57 mi (6,670.04 km) |
| Vila Nova de Gaia to Opelousas (Louisiana) | 4,554.88 mi (7,330.36 km) |
| Vila Nova de Gaia to Orange (California) | 5,581.86 mi (8,983.14 km) |
| Vila Nova de Gaia to Orange (Texas) | 4,652.70 mi (7,487.79 km) |
| Vila Nova de Gaia to Orange City (Florida) | 4,078.57 mi (6,563.82 km) |
| Vila Nova de Gaia to Orangeburg (South Carolina) | 3,891.64 mi (6,262.99 km) |
