| Herndon to Oliveira de Frades | 3,573.64 mi (5,751.22 km) |
| Herndon to Oliveira do Bairro | 3,563.49 mi (5,734.88 km) |
| Herndon to Oliveira do Hospital | 3,598.64 mi (5,791.45 km) |
| Herndon to Ourem | 3,583.16 mi (5,766.54 km) |
| Herndon to Ovar | 3,547.94 mi (5,709.85 km) |
| Herndon to Pacos de Ferreira | 3,548.96 mi (5,711.49 km) |
| Herndon to Palmela | 3,596.15 mi (5,787.44 km) |
| Herndon to Paredes | 3,553.88 mi (5,719.42 km) |
| Herndon to Paredes de Coura | 3,524.85 mi (5,672.70 km) |
| Herndon to Penacova | 3,580.50 mi (5,762.26 km) |
| Herndon to Penafiel | 3,556.11 mi (5,723.00 km) |
| Herndon to Peniche | 3,551.85 mi (5,716.16 km) |
| Herndon to Peso da Regua | 3,581.64 mi (5,764.10 km) |
| Herndon to Pinhal Novo | 3,593.69 mi (5,783.48 km) |
| Herndon to Pinhel | 3,625.92 mi (5,835.35 km) |
