| Riga to Orbetello | 1,152.00 mi (1,853.96 km) |
| Riga to Oria | 1,172.91 mi (1,887.61 km) |
| Riga to Oristano | 1,368.53 mi (2,202.43 km) |
| Riga to Orta Nova | 1,141.85 mi (1,837.64 km) |
| Riga to Orte | 1,126.17 mi (1,812.40 km) |
| Riga to Ortona | 1,095.65 mi (1,763.28 km) |
| Riga to Orvieto | 1,115.47 mi (1,795.18 km) |
| Riga to Orzinuovi | 1,002.65 mi (1,613.60 km) |
| Riga to Osimo | 1,039.43 mi (1,672.79 km) |
| Riga to Ospitaletto | 989.95 mi (1,593.17 km) |
| Riga to Ostuni | 1,157.71 mi (1,863.16 km) |
| Riga to Ottaviano | 1,192.49 mi (1,919.13 km) |
| Riga to Ovada | 1,080.72 mi (1,739.25 km) |
| Riga to Ozieri | 1,316.83 mi (2,119.23 km) |
| Riga to Paceco | 1,412.71 mi (2,273.53 km) |
