| Gresham to Orbetello | 5,725.16 mi (9,213.76 km) |
| Gresham to Oria | 6,002.45 mi (9,660.01 km) |
| Gresham to Oristano | 5,803.45 mi (9,339.76 km) |
| Gresham to Orta Nova | 5,905.34 mi (9,503.73 km) |
| Gresham to Orte | 5,754.18 mi (9,260.46 km) |
| Gresham to Ortona | 5,811.29 mi (9,352.37 km) |
| Gresham to Orvieto | 5,731.72 mi (9,224.31 km) |
| Gresham to Orzinuovi | 5,517.25 mi (8,879.15 km) |
| Gresham to Osimo | 5,720.32 mi (9,205.96 km) |
| Gresham to Ospitaletto | 5,511.68 mi (8,870.19 km) |
| Gresham to Ostuni | 5,986.88 mi (9,634.95 km) |
| Gresham to Ottaviano | 5,904.08 mi (9,501.70 km) |
| Gresham to Ovada | 5,528.39 mi (8,897.09 km) |
| Gresham to Ozieri | 5,775.18 mi (9,294.26 km) |
| Gresham to Paceco | 6,026.70 mi (9,699.03 km) |
