| Osterburg to Navodari | 963.26 mi (1,550.21 km) |
| Osterburg to Negresti-Oas | 615.04 mi (989.82 km) |
| Osterburg to Nehoiu | 832.05 mi (1,339.05 km) |
| Osterburg to Ocna Mures | 697.40 mi (1,122.36 km) |
| Osterburg to Odobesti | 840.29 mi (1,352.32 km) |
| Osterburg to Odorheiu Secuiesc | 751.63 mi (1,209.63 km) |
| Osterburg to Oltenita | 905.51 mi (1,457.28 km) |
| Osterburg to Onesti | 807.49 mi (1,299.53 km) |
| Osterburg to Oradea | 598.75 mi (963.60 km) |
| Osterburg to Orastie | 701.80 mi (1,129.44 km) |
| Osterburg to Oravita | 698.04 mi (1,123.38 km) |
| Osterburg to Orsova | 736.30 mi (1,184.97 km) |
| Osterburg to Otelu Rosu | 692.03 mi (1,113.72 km) |
| Osterburg to Otopeni | 863.01 mi (1,388.88 km) |
| Osterburg to Ovidiu | 963.77 mi (1,551.04 km) |
