| Redwood City to Orbetello | 6,185.65 mi (9,954.83 km) |
| Redwood City to Oria | 6,478.98 mi (10,426.91 km) |
| Redwood City to Oristano | 6,246.99 mi (10,053.56 km) |
| Redwood City to Orta Nova | 6,377.62 mi (10,263.79 km) |
| Redwood City to Orte | 6,218.59 mi (10,007.85 km) |
| Redwood City to Ortona | 6,281.94 mi (10,109.81 km) |
| Redwood City to Orvieto | 6,195.95 mi (9,971.42 km) |
| Redwood City to Orzinuovi | 5,982.30 mi (9,627.58 km) |
| Redwood City to Osimo | 6,191.03 mi (9,963.50 km) |
| Redwood City to Ospitaletto | 5,977.62 mi (9,620.04 km) |
| Redwood City to Ostuni | 6,463.80 mi (10,402.47 km) |
| Redwood City to Ottaviano | 6,371.04 mi (10,253.20 km) |
| Redwood City to Ovada | 5,987.15 mi (9,635.38 km) |
| Redwood City to Ozieri | 6,222.40 mi (10,013.98 km) |
| Redwood City to Paceco | 6,478.83 mi (10,426.67 km) |
