| Darby to Orbetello | 4,291.01 mi (6,905.71 km) |
| Darby to Oria | 4,643.89 mi (7,473.62 km) |
| Darby to Oristano | 4,260.36 mi (6,856.38 km) |
| Darby to Orta Nova | 4,528.50 mi (7,287.92 km) |
| Darby to Orte | 4,341.95 mi (6,987.70 km) |
| Darby to Ortona | 4,433.90 mi (7,135.68 km) |
| Darby to Orvieto | 4,320.83 mi (6,953.70 km) |
| Darby to Orzinuovi | 4,136.25 mi (6,656.65 km) |
| Darby to Osimo | 4,353.74 mi (7,006.66 km) |
| Darby to Ospitaletto | 4,137.22 mi (6,658.22 km) |
| Darby to Ostuni | 4,632.75 mi (7,455.70 km) |
| Darby to Ottaviano | 4,492.05 mi (7,229.26 km) |
| Darby to Ovada | 4,105.14 mi (6,606.58 km) |
| Darby to Ozieri | 4,255.80 mi (6,849.04 km) |
| Darby to Paceco | 4,511.08 mi (7,259.88 km) |
