| Kocaeli to Oerlinghausen | 1,267.13 mi (2,039.25 km) |
| Kocaeli to Oestrich-Winkel | 1,233.58 mi (1,985.25 km) |
| Kocaeli to Offenburg | 1,199.36 mi (1,930.19 km) |
| Kocaeli to Oftersheim | 1,192.90 mi (1,919.78 km) |
| Kocaeli to Ohrdruf | 1,150.88 mi (1,852.16 km) |
| Kocaeli to Ohringen | 1,150.25 mi (1,851.16 km) |
| Kocaeli to Olbernhau | 1,048.56 mi (1,687.50 km) |
| Kocaeli to Olching | 1,047.21 mi (1,685.32 km) |
| Kocaeli to Oldenburg | 1,324.67 mi (2,131.85 km) |
| Kocaeli to Oldenburg in Holstein | 1,281.63 mi (2,062.58 km) |
| Kocaeli to Olfen | 1,307.50 mi (2,104.21 km) |
| Kocaeli to Olpe | 1,268.90 mi (2,042.09 km) |
| Kocaeli to Olsberg | 1,253.87 mi (2,017.91 km) |
| Kocaeli to Oranienburg | 1,139.11 mi (1,833.21 km) |
| Kocaeli to Ortenberg | 1,200.99 mi (1,932.81 km) |
