| Hilo to Orbetello | 8,056.15 mi (12,965.12 km) |
| Hilo to Oria | 8,251.90 mi (13,280.15 km) |
| Hilo to Oristano | 8,186.90 mi (13,175.55 km) |
| Hilo to Orta Nova | 8,179.72 mi (13,163.99 km) |
| Hilo to Orte | 8,069.05 mi (12,985.89 km) |
| Hilo to Ortona | 8,098.19 mi (13,032.77 km) |
| Hilo to Orvieto | 8,048.47 mi (12,952.76 km) |
| Hilo to Orzinuovi | 7,842.11 mi (12,620.65 km) |
| Hilo to Osimo | 8,012.18 mi (12,894.35 km) |
| Hilo to Ospitaletto | 7,833.55 mi (12,606.88 km) |
| Hilo to Ostuni | 8,235.57 mi (13,253.87 km) |
| Hilo to Ottaviano | 8,200.64 mi (13,197.65 km) |
| Hilo to Ovada | 7,875.20 mi (12,673.91 km) |
| Hilo to Ozieri | 8,148.53 mi (13,113.80 km) |
| Hilo to Paceco | 8,371.95 mi (13,473.35 km) |
