| Estoril to Orbetello | 1,109.06 mi (1,784.85 km) |
| Estoril to Oria | 1,438.74 mi (2,315.42 km) |
| Estoril to Oristano | 963.74 mi (1,550.98 km) |
| Estoril to Orta Nova | 1,336.25 mi (2,150.49 km) |
| Estoril to Orte | 1,168.71 mi (1,880.86 km) |
| Estoril to Ortona | 1,270.55 mi (2,044.75 km) |
| Estoril to Orvieto | 1,156.64 mi (1,861.43 km) |
| Estoril to Orzinuovi | 1,090.70 mi (1,755.31 km) |
| Estoril to Osimo | 1,231.96 mi (1,982.65 km) |
| Estoril to Ospitaletto | 1,100.53 mi (1,771.12 km) |
| Estoril to Ostuni | 1,435.12 mi (2,309.60 km) |
| Estoril to Ottaviano | 1,272.47 mi (2,047.85 km) |
| Estoril to Ovada | 1,014.72 mi (1,633.04 km) |
| Estoril to Ozieri | 985.77 mi (1,586.44 km) |
| Estoril to Paceco | 1,187.58 mi (1,911.23 km) |
