| Irlam to Orbetello | 984.73 mi (1,584.76 km) |
| Irlam to Oria | 1,293.12 mi (2,081.08 km) |
| Irlam to Oristano | 1,068.50 mi (1,719.59 km) |
| Irlam to Orta Nova | 1,185.18 mi (1,907.36 km) |
| Irlam to Orte | 1,018.53 mi (1,639.16 km) |
| Irlam to Ortona | 1,087.95 mi (1,750.88 km) |
| Irlam to Orvieto | 995.85 mi (1,602.66 km) |
| Irlam to Orzinuovi | 783.62 mi (1,261.11 km) |
| Irlam to Osimo | 998.18 mi (1,606.42 km) |
| Irlam to Ospitaletto | 779.92 mi (1,255.16 km) |
| Irlam to Ostuni | 1,279.05 mi (2,058.43 km) |
| Irlam to Ottaviano | 1,172.20 mi (1,886.48 km) |
| Irlam to Ovada | 786.49 mi (1,265.73 km) |
| Irlam to Ozieri | 1,035.98 mi (1,667.25 km) |
| Irlam to Paceco | 1,283.84 mi (2,066.15 km) |
