| Portimao to Oswego (Illinois) | 4,113.87 mi (6,620.63 km) |
| Portimao to Oswego (New York) | 3,508.28 mi (5,646.03 km) |
| Portimao to Otsego (Minnesota) | 4,250.06 mi (6,839.81 km) |
| Portimao to Ottawa (Illinois) | 4,146.31 mi (6,672.84 km) |
| Portimao to Ottawa (Kansas) | 4,536.30 mi (7,300.46 km) |
| Portimao to Ottumwa (Iowa) | 4,324.56 mi (6,959.71 km) |
| Portimao to Overland (Missouri) | 4,299.97 mi (6,920.14 km) |
| Portimao to Overland Park (Kansas) | 4,499.50 mi (7,241.24 km) |
| Portimao to Overlea (Maryland) | 3,601.19 mi (5,795.56 km) |
| Portimao to Oviedo (Florida) | 4,154.03 mi (6,685.27 km) |
| Portimao to Owasso (Oklahoma) | 4,642.46 mi (7,471.32 km) |
| Portimao to Owatonna (Minnesota) | 4,267.81 mi (6,868.38 km) |
| Portimao to Owensboro (Kentucky) | 4,170.80 mi (6,712.26 km) |
| Portimao to Owings Mills (Maryland) | 3,613.73 mi (5,815.74 km) |
| Portimao to Owosso (Michigan) | 3,882.85 mi (6,248.85 km) |
