| Alenquer to Oerlinghausen | 1,230.40 mi (1,980.14 km) |
| Alenquer to Oestrich-Winkel | 1,124.34 mi (1,809.45 km) |
| Alenquer to Offenburg | 1,063.14 mi (1,710.95 km) |
| Alenquer to Oftersheim | 1,121.41 mi (1,804.73 km) |
| Alenquer to Ohrdruf | 1,255.98 mi (2,021.31 km) |
| Alenquer to Ohringen | 1,150.31 mi (1,851.24 km) |
| Alenquer to Olbernhau | 1,348.53 mi (2,170.25 km) |
| Alenquer to Olching | 1,191.85 mi (1,918.10 km) |
| Alenquer to Oldenburg | 1,269.85 mi (2,043.63 km) |
| Alenquer to Oldenburg in Holstein | 1,404.44 mi (2,260.22 km) |
| Alenquer to Olfen | 1,177.54 mi (1,895.06 km) |
| Alenquer to Olpe | 1,161.13 mi (1,868.65 km) |
| Alenquer to Olsberg | 1,197.50 mi (1,927.18 km) |
| Alenquer to Oranienburg | 1,418.11 mi (2,282.22 km) |
| Alenquer to Ortenberg | 1,176.66 mi (1,893.65 km) |
