| Bologna to Oerlinghausen | 530.71 mi (854.10 km) |
| Bologna to Oestrich-Winkel | 411.37 mi (662.03 km) |
| Bologna to Offenburg | 318.77 mi (513.00 km) |
| Bologna to Oftersheim | 361.14 mi (581.19 km) |
| Bologna to Ohrdruf | 438.57 mi (705.80 km) |
| Bologna to Ohringen | 336.59 mi (541.69 km) |
| Bologna to Olbernhau | 436.43 mi (702.36 km) |
| Bologna to Olching | 256.07 mi (412.10 km) |
| Bologna to Oldenburg | 614.22 mi (988.49 km) |
| Bologna to Oldenburg in Holstein | 677.85 mi (1,090.89 km) |
| Bologna to Olfen | 531.23 mi (854.93 km) |
| Bologna to Olpe | 479.12 mi (771.06 km) |
| Bologna to Olsberg | 491.76 mi (791.42 km) |
| Bologna to Oranienburg | 577.21 mi (928.93 km) |
| Bologna to Ortenberg | 418.84 mi (674.06 km) |
