| Flensburg to Oestrich-Winkel | 335.89 mi (540.56 km) |
| Flensburg to Offenburg | 441.05 mi (709.80 km) |
| Flensburg to Oftersheim | 375.62 mi (604.51 km) |
| Flensburg to Ohrdruf | 278.48 mi (448.17 km) |
| Flensburg to Ohringen | 385.68 mi (620.69 km) |
| Flensburg to Olbernhau | 327.65 mi (527.31 km) |
| Flensburg to Olching | 461.86 mi (743.29 km) |
| Flensburg to Oldenburg | 123.60 mi (198.92 km) |
| Flensburg to Oldenburg in Holstein | 66.86 mi (107.60 km) |
| Flensburg to Olfen | 228.14 mi (367.15 km) |
| Flensburg to Olpe | 268.58 mi (432.23 km) |
| Flensburg to Olsberg | 240.40 mi (386.88 km) |
| Flensburg to Oranienburg | 209.01 mi (336.37 km) |
| Flensburg to Ortenberg | 306.23 mi (492.83 km) |
| Flensburg to Oschatz | 284.72 mi (458.22 km) |
