| Karlovo to Oestrich-Winkel | 946.21 mi (1,522.77 km) |
| Karlovo to Offenburg | 907.48 mi (1,460.44 km) |
| Karlovo to Oftersheim | 903.93 mi (1,454.73 km) |
| Karlovo to Ohrdruf | 871.48 mi (1,402.51 km) |
| Karlovo to Ohringen | 861.60 mi (1,386.61 km) |
| Karlovo to Olbernhau | 775.08 mi (1,247.37 km) |
| Karlovo to Olching | 756.98 mi (1,218.25 km) |
| Karlovo to Oldenburg | 1,052.27 mi (1,693.47 km) |
| Karlovo to Oldenburg in Holstein | 1,023.50 mi (1,647.16 km) |
| Karlovo to Olfen | 1,026.39 mi (1,651.82 km) |
| Karlovo to Olpe | 985.36 mi (1,585.78 km) |
| Karlovo to Olsberg | 972.83 mi (1,565.62 km) |
| Karlovo to Oranienburg | 879.48 mi (1,415.39 km) |
| Karlovo to Ortenberg | 916.33 mi (1,474.70 km) |
| Karlovo to Oschatz | 811.72 mi (1,306.33 km) |
