| Penafiel to Oswego (Illinois) | 3,982.97 mi (6,409.97 km) |
| Penafiel to Oswego (New York) | 3,387.21 mi (5,451.19 km) |
| Penafiel to Otsego (Minnesota) | 4,094.98 mi (6,590.23 km) |
| Penafiel to Ottawa (Illinois) | 4,016.06 mi (6,463.22 km) |
| Penafiel to Ottawa (Kansas) | 4,406.11 mi (7,090.94 km) |
| Penafiel to Ottumwa (Iowa) | 4,189.49 mi (6,742.33 km) |
| Penafiel to Overland (Missouri) | 4,178.81 mi (6,725.14 km) |
| Penafiel to Overland Park (Kansas) | 4,369.23 mi (7,031.60 km) |
| Penafiel to Overlea (Maryland) | 3,502.34 mi (5,636.47 km) |
| Penafiel to Oviedo (Florida) | 4,099.65 mi (6,597.75 km) |
| Penafiel to Owasso (Oklahoma) | 4,520.62 mi (7,275.23 km) |
| Penafiel to Owatonna (Minnesota) | 4,118.28 mi (6,627.73 km) |
| Penafiel to Owensboro (Kentucky) | 4,060.16 mi (6,534.20 km) |
| Penafiel to Owings Mills (Maryland) | 3,514.13 mi (5,655.45 km) |
| Penafiel to Owosso (Michigan) | 3,752.60 mi (6,039.23 km) |
