| Ciechanow to Navodari | 693.03 mi (1,115.32 km) |
| Ciechanow to Negresti-Oas | 366.46 mi (589.76 km) |
| Ciechanow to Nehoiu | 578.63 mi (931.21 km) |
| Ciechanow to Ocna Mures | 470.10 mi (756.55 km) |
| Ciechanow to Odobesti | 569.23 mi (916.08 km) |
| Ciechanow to Odorheiu Secuiesc | 498.45 mi (802.17 km) |
| Ciechanow to Oltenita | 665.48 mi (1,070.99 km) |
| Ciechanow to Onesti | 532.54 mi (857.05 km) |
| Ciechanow to Oradea | 404.41 mi (650.84 km) |
| Ciechanow to Orastie | 498.29 mi (801.92 km) |
| Ciechanow to Oravita | 542.84 mi (873.61 km) |
| Ciechanow to Orsova | 568.16 mi (914.37 km) |
| Ciechanow to Otelu Rosu | 513.57 mi (826.51 km) |
| Ciechanow to Otopeni | 625.37 mi (1,006.44 km) |
| Ciechanow to Ovidiu | 694.86 mi (1,118.28 km) |
