| Montemor-o-Velho to Oerlinghausen | 1,159.04 mi (1,865.30 km) |
| Montemor-o-Velho to Oestrich-Winkel | 1,056.00 mi (1,699.47 km) |
| Montemor-o-Velho to Offenburg | 998.39 mi (1,606.75 km) |
| Montemor-o-Velho to Oftersheim | 1,055.03 mi (1,697.91 km) |
| Montemor-o-Velho to Ohrdruf | 1,188.29 mi (1,912.37 km) |
| Montemor-o-Velho to Ohringen | 1,085.19 mi (1,746.45 km) |
| Montemor-o-Velho to Olbernhau | 1,283.09 mi (2,064.93 km) |
| Montemor-o-Velho to Olching | 1,130.94 mi (1,820.08 km) |
| Montemor-o-Velho to Oldenburg | 1,196.51 mi (1,925.59 km) |
| Montemor-o-Velho to Oldenburg in Holstein | 1,331.36 mi (2,142.62 km) |
| Montemor-o-Velho to Olfen | 1,105.55 mi (1,779.20 km) |
| Montemor-o-Velho to Olpe | 1,090.67 mi (1,755.27 km) |
| Montemor-o-Velho to Olsberg | 1,127.01 mi (1,813.74 km) |
| Montemor-o-Velho to Oranienburg | 1,348.68 mi (2,170.49 km) |
| Montemor-o-Velho to Ortenberg | 1,108.54 mi (1,784.02 km) |
