| Houma to Orbetello | 5,418.98 mi (8,721.00 km) |
| Houma to Oria | 5,772.01 mi (9,289.16 km) |
| Houma to Oristano | 5,385.27 mi (8,666.76 km) |
| Houma to Orta Nova | 5,656.62 mi (9,103.45 km) |
| Houma to Orte | 5,470.04 mi (8,803.18 km) |
| Houma to Ortona | 5,562.01 mi (8,951.19 km) |
| Houma to Orvieto | 5,448.93 mi (8,769.21 km) |
| Houma to Orzinuovi | 5,264.05 mi (8,471.67 km) |
| Houma to Osimo | 5,481.71 mi (8,821.96 km) |
| Houma to Ospitaletto | 5,264.92 mi (8,473.07 km) |
| Houma to Ostuni | 5,760.87 mi (9,271.22 km) |
| Houma to Ottaviano | 5,619.99 mi (9,044.50 km) |
| Houma to Ovada | 5,233.26 mi (8,422.11 km) |
| Houma to Ozieri | 5,381.78 mi (8,661.14 km) |
| Houma to Paceco | 5,635.85 mi (9,070.02 km) |
