| Leiden to Orbetello | 741.06 mi (1,192.62 km) |
| Leiden to Oria | 1,017.59 mi (1,637.66 km) |
| Leiden to Oristano | 868.88 mi (1,398.32 km) |
| Leiden to Orta Nova | 915.38 mi (1,473.17 km) |
| Leiden to Orte | 764.45 mi (1,230.26 km) |
| Leiden to Ortona | 820.20 mi (1,319.99 km) |
| Leiden to Orvieto | 742.28 mi (1,194.58 km) |
| Leiden to Orzinuovi | 528.39 mi (850.36 km) |
| Leiden to Osimo | 729.20 mi (1,173.53 km) |
| Leiden to Ospitaletto | 521.81 mi (839.77 km) |
| Leiden to Ostuni | 1,002.70 mi (1,613.69 km) |
| Leiden to Ottaviano | 912.56 mi (1,468.63 km) |
| Leiden to Ovada | 553.28 mi (890.41 km) |
| Leiden to Ozieri | 827.78 mi (1,332.18 km) |
| Leiden to Paceco | 1,053.95 mi (1,696.17 km) |
