| Darlington to Orbetello | 1,016.05 mi (1,635.17 km) |
| Darlington to Oria | 1,310.91 mi (2,109.70 km) |
| Darlington to Oristano | 1,114.15 mi (1,793.05 km) |
| Darlington to Orta Nova | 1,205.91 mi (1,940.72 km) |
| Darlington to Orte | 1,045.96 mi (1,683.30 km) |
| Darlington to Ortona | 1,109.47 mi (1,785.52 km) |
| Darlington to Orvieto | 1,023.39 mi (1,646.98 km) |
| Darlington to Orzinuovi | 809.25 mi (1,302.36 km) |
| Darlington to Osimo | 1,018.82 mi (1,639.63 km) |
| Darlington to Ospitaletto | 804.36 mi (1,294.49 km) |
| Darlington to Ostuni | 1,296.34 mi (2,086.25 km) |
| Darlington to Ottaviano | 1,197.78 mi (1,927.64 km) |
| Darlington to Ovada | 820.05 mi (1,319.75 km) |
| Darlington to Ozieri | 1,079.05 mi (1,736.57 km) |
| Darlington to Paceco | 1,321.27 mi (2,126.39 km) |
