| Willow Grove to Orbetello | 4,276.06 mi (6,881.65 km) |
| Willow Grove to Oria | 4,628.80 mi (7,449.33 km) |
| Willow Grove to Oristano | 4,246.00 mi (6,833.28 km) |
| Willow Grove to Orta Nova | 4,513.42 mi (7,263.65 km) |
| Willow Grove to Orte | 4,326.93 mi (6,963.52 km) |
| Willow Grove to Ortona | 4,418.77 mi (7,111.32 km) |
| Willow Grove to Orvieto | 4,305.79 mi (6,929.49 km) |
| Willow Grove to Orzinuovi | 4,120.94 mi (6,632.02 km) |
| Willow Grove to Osimo | 4,338.50 mi (6,982.14 km) |
| Willow Grove to Ospitaletto | 4,121.89 mi (6,633.53 km) |
| Willow Grove to Ostuni | 4,617.63 mi (7,431.36 km) |
| Willow Grove to Ottaviano | 4,477.13 mi (7,205.24 km) |
| Willow Grove to Ovada | 4,090.02 mi (6,582.25 km) |
| Willow Grove to Ozieri | 4,241.29 mi (6,825.70 km) |
| Willow Grove to Paceco | 4,496.73 mi (7,236.79 km) |
