| Grevenmacher to Orbetello | 549.84 mi (884.89 km) |
| Grevenmacher to Oria | 835.07 mi (1,343.92 km) |
| Grevenmacher to Oristano | 683.47 mi (1,099.94 km) |
| Grevenmacher to Orta Nova | 729.81 mi (1,174.52 km) |
| Grevenmacher to Orte | 574.09 mi (923.90 km) |
| Grevenmacher to Ortona | 633.56 mi (1,019.61 km) |
| Grevenmacher to Orvieto | 551.80 mi (888.03 km) |
| Grevenmacher to Orzinuovi | 337.54 mi (543.23 km) |
| Grevenmacher to Osimo | 542.79 mi (873.54 km) |
| Grevenmacher to Ospitaletto | 331.34 mi (533.24 km) |
| Grevenmacher to Ostuni | 820.64 mi (1,320.69 km) |
| Grevenmacher to Ottaviano | 723.61 mi (1,164.55 km) |
| Grevenmacher to Ovada | 363.36 mi (584.77 km) |
| Grevenmacher to Ozieri | 640.63 mi (1,031.00 km) |
| Grevenmacher to Paceco | 862.92 mi (1,388.73 km) |
