| Norridge to Orbetello | 4,739.11 mi (7,626.87 km) |
| Norridge to Oria | 5,080.18 mi (8,175.76 km) |
| Norridge to Oristano | 4,738.27 mi (7,625.51 km) |
| Norridge to Orta Nova | 4,966.82 mi (7,993.32 km) |
| Norridge to Orte | 4,785.23 mi (7,701.08 km) |
| Norridge to Ortona | 4,869.84 mi (7,837.25 km) |
| Norridge to Orvieto | 4,763.16 mi (7,665.56 km) |
| Norridge to Orzinuovi | 4,564.91 mi (7,346.51 km) |
| Norridge to Osimo | 4,784.43 mi (7,699.79 km) |
| Norridge to Ospitaletto | 4,564.02 mi (7,345.09 km) |
| Norridge to Ostuni | 5,067.52 mi (8,155.38 km) |
| Norridge to Ottaviano | 4,939.22 mi (7,948.91 km) |
| Norridge to Ovada | 4,545.08 mi (7,314.60 km) |
| Norridge to Ozieri | 4,726.97 mi (7,607.33 km) |
| Norridge to Paceco | 4,987.32 mi (8,026.32 km) |
