| Hartlepool to Oerlinghausen | 448.38 mi (721.59 km) |
| Hartlepool to Oestrich-Winkel | 505.39 mi (813.35 km) |
| Hartlepool to Offenburg | 581.33 mi (935.56 km) |
| Hartlepool to Oftersheim | 554.47 mi (892.34 km) |
| Hartlepool to Ohrdruf | 565.16 mi (909.54 km) |
| Hartlepool to Ohringen | 592.15 mi (952.97 km) |
| Hartlepool to Olbernhau | 668.01 mi (1,075.05 km) |
| Hartlepool to Olching | 699.70 mi (1,126.06 km) |
| Hartlepool to Oldenburg | 397.74 mi (640.10 km) |
| Hartlepool to Oldenburg in Holstein | 485.42 mi (781.21 km) |
| Hartlepool to Olfen | 410.30 mi (660.32 km) |
| Hartlepool to Olpe | 454.19 mi (730.94 km) |
| Hartlepool to Olsberg | 463.71 mi (746.27 km) |
| Hartlepool to Oranienburg | 604.40 mi (972.70 km) |
| Hartlepool to Ortenberg | 524.46 mi (844.03 km) |
