| Derry to Orbetello | 1,204.19 mi (1,937.95 km) |
| Derry to Oria | 1,517.85 mi (2,442.75 km) |
| Derry to Oristano | 1,274.40 mi (2,050.95 km) |
| Derry to Orta Nova | 1,409.20 mi (2,267.89 km) |
| Derry to Orte | 1,240.10 mi (1,995.74 km) |
| Derry to Ortona | 1,311.82 mi (2,111.17 km) |
| Derry to Orvieto | 1,217.41 mi (1,959.24 km) |
| Derry to Orzinuovi | 1,006.56 mi (1,619.91 km) |
| Derry to Osimo | 1,222.43 mi (1,967.31 km) |
| Derry to Ospitaletto | 1,003.32 mi (1,614.70 km) |
| Derry to Ostuni | 1,503.90 mi (2,420.29 km) |
| Derry to Ottaviano | 1,394.38 mi (2,244.05 km) |
| Derry to Ovada | 1,005.28 mi (1,617.84 km) |
| Derry to Ozieri | 1,245.11 mi (2,003.80 km) |
| Derry to Paceco | 1,497.71 mi (2,410.33 km) |
