| Hwlffordd to Oerlinghausen | 580.85 mi (934.79 km) |
| Hwlffordd to Oestrich-Winkel | 577.86 mi (929.97 km) |
| Hwlffordd to Offenburg | 615.08 mi (989.88 km) |
| Hwlffordd to Oftersheim | 616.84 mi (992.71 km) |
| Hwlffordd to Ohrdruf | 680.14 mi (1,094.57 km) |
| Hwlffordd to Ohringen | 659.57 mi (1,061.47 km) |
| Hwlffordd to Olbernhau | 793.60 mi (1,277.17 km) |
| Hwlffordd to Olching | 762.96 mi (1,227.86 km) |
| Hwlffordd to Oldenburg | 561.76 mi (904.07 km) |
| Hwlffordd to Oldenburg in Holstein | 679.10 mi (1,092.91 km) |
| Hwlffordd to Olfen | 527.72 mi (849.28 km) |
| Hwlffordd to Olpe | 553.72 mi (891.13 km) |
| Hwlffordd to Olsberg | 577.71 mi (929.73 km) |
| Hwlffordd to Oranienburg | 770.42 mi (1,239.88 km) |
| Hwlffordd to Ortenberg | 615.95 mi (991.27 km) |
