| Sliven to Oegstgeest | 1,207.28 mi (1,942.93 km) |
| Sliven to Oirschot | 1,155.63 mi (1,859.81 km) |
| Sliven to Oisterwijk | 1,161.87 mi (1,869.86 km) |
| Sliven to Oldebroek | 1,160.80 mi (1,868.13 km) |
| Sliven to Oldenzaal | 1,118.02 mi (1,799.28 km) |
| Sliven to Ommen | 1,143.75 mi (1,840.69 km) |
| Sliven to Oosterend | 1,172.83 mi (1,887.49 km) |
| Sliven to Oosterhout | 1,177.02 mi (1,894.24 km) |
| Sliven to Oosterwolde | 1,164.23 mi (1,873.65 km) |
| Sliven to Oostzaan | 1,198.60 mi (1,928.97 km) |
| Sliven to Opmeer | 1,204.19 mi (1,937.95 km) |
| Sliven to Oss | 1,154.68 mi (1,858.28 km) |
| Sliven to Oud-Beijerland | 1,199.72 mi (1,930.76 km) |
| Sliven to Oudenbosch | 1,188.73 mi (1,913.08 km) |
| Sliven to Oudewater | 1,187.07 mi (1,910.40 km) |
