| Montemor-o-Novo to Oakley (California) | 5,665.35 mi (9,117.50 km) |
| Montemor-o-Novo to Oakton (Virginia) | 3,625.65 mi (5,834.92 km) |
| Montemor-o-Novo to Oakville (Missouri) | 4,270.70 mi (6,873.03 km) |
| Montemor-o-Novo to Oatfield (Oregon) | 5,346.31 mi (8,604.06 km) |
| Montemor-o-Novo to Ocala (Florida) | 4,176.66 mi (6,721.68 km) |
| Montemor-o-Novo to Ocean Acres (New Jersey) | 3,453.84 mi (5,558.41 km) |
| Montemor-o-Novo to Ocean City (New Jersey) | 3,481.81 mi (5,603.43 km) |
| Montemor-o-Novo to Ocean Pines (Maryland) | 3,532.10 mi (5,684.37 km) |
| Montemor-o-Novo to Ocean Pointe (Hawaii) | 7,855.56 mi (12,642.30 km) |
| Montemor-o-Novo to Ocean Springs (Mississippi) | 4,474.14 mi (7,200.44 km) |
| Montemor-o-Novo to Oceanside (California) | 5,708.17 mi (9,186.42 km) |
| Montemor-o-Novo to Oceanside (New York) | 3,400.25 mi (5,472.17 km) |
| Montemor-o-Novo to Ocoee (Florida) | 4,165.39 mi (6,703.54 km) |
| Montemor-o-Novo to Oconomowoc (Wisconsin) | 4,039.45 mi (6,500.87 km) |
| Montemor-o-Novo to Odenton (Maryland) | 3,590.81 mi (5,778.85 km) |
