| Sligo to Navodari | 1,781.75 mi (2,867.45 km) |
| Sligo to Negresti-Oas | 1,439.90 mi (2,317.30 km) |
| Sligo to Nehoiu | 1,648.25 mi (2,652.59 km) |
| Sligo to Ocna Mures | 1,510.65 mi (2,431.16 km) |
| Sligo to Odobesti | 1,662.76 mi (2,675.95 km) |
| Sligo to Odorheiu Secuiesc | 1,571.23 mi (2,528.66 km) |
| Sligo to Oltenita | 1,712.46 mi (2,755.94 km) |
| Sligo to Onesti | 1,632.21 mi (2,626.79 km) |
| Sligo to Oradea | 1,407.88 mi (2,265.76 km) |
| Sligo to Orastie | 1,504.98 mi (2,422.03 km) |
| Sligo to Oravita | 1,477.39 mi (2,377.64 km) |
| Sligo to Orsova | 1,518.31 mi (2,443.48 km) |
| Sligo to Otelu Rosu | 1,484.40 mi (2,388.91 km) |
| Sligo to Otopeni | 1,670.92 mi (2,689.09 km) |
| Sligo to Ovidiu | 1,781.69 mi (2,867.36 km) |
