| Simi Valley to Orbetello | 6,265.02 mi (10,082.57 km) |
| Simi Valley to Oria | 6,572.33 mi (10,577.15 km) |
| Simi Valley to Oristano | 6,310.73 mi (10,156.13 km) |
| Simi Valley to Orta Nova | 6,467.27 mi (10,408.07 km) |
| Simi Valley to Orte | 6,301.47 mi (10,141.23 km) |
| Simi Valley to Ortona | 6,370.48 mi (10,252.29 km) |
| Simi Valley to Orvieto | 6,278.79 mi (10,104.73 km) |
| Simi Valley to Orzinuovi | 6,067.04 mi (9,763.96 km) |
| Simi Valley to Osimo | 6,280.10 mi (10,106.85 km) |
| Simi Valley to Ospitaletto | 6,063.22 mi (9,757.81 km) |
| Simi Valley to Ostuni | 6,557.61 mi (10,553.46 km) |
| Simi Valley to Ottaviano | 6,455.55 mi (10,389.20 km) |
| Simi Valley to Ovada | 6,065.99 mi (9,762.27 km) |
| Simi Valley to Ozieri | 6,289.52 mi (10,122.00 km) |
| Simi Valley to Paceco | 6,548.91 mi (10,539.46 km) |
