| Olgiate Olona to Oria | 565.88 mi (910.70 km) |
| Olgiate Olona to Oristano | 396.01 mi (637.31 km) |
| Olgiate Olona to Orta Nova | 453.08 mi (729.16 km) |
| Olgiate Olona to Orte | 279.80 mi (450.30 km) |
| Olgiate Olona to Ortona | 355.75 mi (572.52 km) |
| Olgiate Olona to Orvieto | 257.12 mi (413.80 km) |
| Olgiate Olona to Orzinuovi | 53.33 mi (85.82 km) |
| Olgiate Olona to Osimo | 270.77 mi (435.76 km) |
| Olgiate Olona to Ospitaletto | 57.78 mi (92.99 km) |
| Olgiate Olona to Ostuni | 553.30 mi (890.45 km) |
| Olgiate Olona to Ottaviano | 433.95 mi (698.37 km) |
| Olgiate Olona to Ovada | 69.65 mi (112.09 km) |
| Olgiate Olona to Ozieri | 348.86 mi (561.44 km) |
| Olgiate Olona to Paceco | 561.12 mi (903.03 km) |
| Olgiate Olona to Pachino | 695.23 mi (1,118.86 km) |
