| Opmeer to Oliveira do Bairro | 1,052.84 mi (1,694.39 km) |
| Opmeer to Oliveira do Hospital | 1,044.49 mi (1,680.94 km) |
| Opmeer to Ourem | 1,105.66 mi (1,779.39 km) |
| Opmeer to Ovar | 1,036.33 mi (1,667.81 km) |
| Opmeer to Pacos de Ferreira | 1,006.58 mi (1,619.94 km) |
| Opmeer to Palmela | 1,179.32 mi (1,897.93 km) |
| Opmeer to Paredes | 1,008.50 mi (1,623.02 km) |
| Opmeer to Paredes de Coura | 974.63 mi (1,568.52 km) |
| Opmeer to Penacova | 1,061.22 mi (1,707.87 km) |
| Opmeer to Penafiel | 1,006.74 mi (1,620.19 km) |
| Opmeer to Peniche | 1,145.53 mi (1,843.56 km) |
| Opmeer to Peso da Regua | 994.73 mi (1,600.87 km) |
| Opmeer to Pinhal Novo | 1,175.83 mi (1,892.32 km) |
| Opmeer to Pinhel | 997.95 mi (1,606.04 km) |
| Opmeer to Pombal | 1,091.63 mi (1,756.80 km) |
