| Portales to Orbetello | 5,721.47 mi (9,207.81 km) |
| Portales to Oria | 6,056.44 mi (9,746.91 km) |
| Portales to Oristano | 5,729.61 mi (9,220.91 km) |
| Portales to Orta Nova | 5,944.47 mi (9,566.70 km) |
| Portales to Orte | 5,765.65 mi (9,278.92 km) |
| Portales to Ortona | 5,847.07 mi (9,409.95 km) |
| Portales to Orvieto | 5,743.34 mi (9,243.02 km) |
| Portales to Orzinuovi | 5,540.98 mi (8,917.34 km) |
| Portales to Osimo | 5,760.05 mi (9,269.90 km) |
| Portales to Ospitaletto | 5,539.37 mi (8,914.76 km) |
| Portales to Ostuni | 6,043.23 mi (9,725.64 km) |
| Portales to Ottaviano | 5,920.34 mi (9,527.87 km) |
| Portales to Ovada | 5,525.48 mi (8,892.39 km) |
| Portales to Ozieri | 5,716.57 mi (9,199.92 km) |
| Portales to Paceco | 5,977.53 mi (9,619.91 km) |
