| Eureka to Orbetello | 6,046.99 mi (9,731.69 km) |
| Eureka to Oria | 6,329.33 mi (10,186.07 km) |
| Eureka to Oristano | 6,119.63 mi (9,848.59 km) |
| Eureka to Orta Nova | 6,230.93 mi (10,027.72 km) |
| Eureka to Orte | 6,077.28 mi (9,780.43 km) |
| Eureka to Ortona | 6,136.34 mi (9,875.49 km) |
| Eureka to Orvieto | 6,054.75 mi (9,744.17 km) |
| Eureka to Orzinuovi | 5,840.40 mi (9,399.21 km) |
| Eureka to Osimo | 6,045.34 mi (9,729.03 km) |
| Eureka to Ospitaletto | 5,835.11 mi (9,390.69 km) |
| Eureka to Ostuni | 6,313.86 mi (10,161.18 km) |
| Eureka to Ottaviano | 6,228.06 mi (10,023.09 km) |
| Eureka to Ovada | 5,849.53 mi (9,413.90 km) |
| Eureka to Ozieri | 6,092.61 mi (9,805.11 km) |
| Eureka to Paceco | 6,345.98 mi (10,212.88 km) |
