| Tallaght to Oria | 1,424.83 mi (2,293.04 km) |
| Tallaght to Oristano | 1,160.68 mi (1,867.93 km) |
| Tallaght to Orta Nova | 1,314.06 mi (2,114.77 km) |
| Tallaght to Orte | 1,140.22 mi (1,835.01 km) |
| Tallaght to Ortona | 1,216.51 mi (1,957.78 km) |
| Tallaght to Orvieto | 1,117.61 mi (1,798.61 km) |
| Tallaght to Orzinuovi | 910.19 mi (1,464.81 km) |
| Tallaght to Osimo | 1,128.47 mi (1,816.09 km) |
| Tallaght to Ospitaletto | 907.99 mi (1,461.26 km) |
| Tallaght to Ostuni | 1,411.39 mi (2,271.41 km) |
| Tallaght to Ottaviano | 1,295.14 mi (2,084.32 km) |
| Tallaght to Ovada | 902.49 mi (1,452.41 km) |
| Tallaght to Ozieri | 1,133.28 mi (1,823.84 km) |
| Tallaght to Paceco | 1,388.58 mi (2,234.71 km) |
| Tallaght to Pachino | 1,540.35 mi (2,478.96 km) |
