| Highland Park to Orbetello | 4,729.21 mi (7,610.93 km) |
| Highland Park to Oria | 5,069.95 mi (8,159.29 km) |
| Highland Park to Oristano | 4,729.07 mi (7,610.71 km) |
| Highland Park to Orta Nova | 4,956.65 mi (7,976.96 km) |
| Highland Park to Orte | 4,775.21 mi (7,684.96 km) |
| Highland Park to Ortona | 4,859.64 mi (7,820.84 km) |
| Highland Park to Orvieto | 4,753.13 mi (7,649.42 km) |
| Highland Park to Orzinuovi | 4,554.63 mi (7,329.96 km) |
| Highland Park to Osimo | 4,774.14 mi (7,683.23 km) |
| Highland Park to Ospitaletto | 4,553.70 mi (7,328.48 km) |
| Highland Park to Ostuni | 5,057.25 mi (8,138.86 km) |
| Highland Park to Ottaviano | 4,929.26 mi (7,932.87 km) |
| Highland Park to Ovada | 4,535.04 mi (7,298.45 km) |
| Highland Park to Ozieri | 4,717.61 mi (7,592.27 km) |
| Highland Park to Paceco | 4,978.03 mi (8,011.37 km) |
