| Hopatcong to Orbetello | 4,225.45 mi (6,800.21 km) |
| Hopatcong to Oria | 4,577.59 mi (7,366.92 km) |
| Hopatcong to Oristano | 4,197.62 mi (6,755.42 km) |
| Hopatcong to Orta Nova | 4,462.28 mi (7,181.35 km) |
| Hopatcong to Orte | 4,276.02 mi (6,881.59 km) |
| Hopatcong to Ortona | 4,367.42 mi (7,028.68 km) |
| Hopatcong to Orvieto | 4,254.80 mi (6,847.44 km) |
| Hopatcong to Orzinuovi | 4,068.95 mi (6,548.34 km) |
| Hopatcong to Osimo | 4,286.76 mi (6,898.88 km) |
| Hopatcong to Ospitaletto | 4,069.77 mi (6,549.67 km) |
| Hopatcong to Ostuni | 4,566.31 mi (7,348.77 km) |
| Hopatcong to Ottaviano | 4,426.57 mi (7,123.88 km) |
| Hopatcong to Ovada | 4,038.74 mi (6,499.72 km) |
| Hopatcong to Ozieri | 4,192.37 mi (6,746.97 km) |
| Hopatcong to Paceco | 4,448.36 mi (7,158.95 km) |
