| Potomac to Oliveira de Frades | 3,563.00 mi (5,734.10 km) |
| Potomac to Oliveira do Bairro | 3,552.84 mi (5,717.74 km) |
| Potomac to Oliveira do Hospital | 3,587.99 mi (5,774.31 km) |
| Potomac to Ourem | 3,572.48 mi (5,749.35 km) |
| Potomac to Ovar | 3,537.29 mi (5,692.72 km) |
| Potomac to Pacos de Ferreira | 3,538.33 mi (5,694.40 km) |
| Potomac to Palmela | 3,585.44 mi (5,770.20 km) |
| Potomac to Paredes | 3,543.26 mi (5,702.32 km) |
| Potomac to Paredes de Coura | 3,514.25 mi (5,655.64 km) |
| Potomac to Penacova | 3,569.84 mi (5,745.11 km) |
| Potomac to Penafiel | 3,545.48 mi (5,705.90 km) |
| Potomac to Peniche | 3,541.16 mi (5,698.94 km) |
| Potomac to Peso da Regua | 3,571.02 mi (5,747.01 km) |
| Potomac to Pinhal Novo | 3,582.98 mi (5,766.24 km) |
| Potomac to Pinhel | 3,615.29 mi (5,818.25 km) |
