| West Allis to Nuth | 4,154.76 mi (6,686.44 km) |
| West Allis to Oegstgeest | 4,056.78 mi (6,528.76 km) |
| West Allis to Oirschot | 4,111.84 mi (6,617.37 km) |
| West Allis to Oisterwijk | 4,105.15 mi (6,606.60 km) |
| West Allis to Oldebroek | 4,098.68 mi (6,596.18 km) |
| West Allis to Oldenzaal | 4,140.43 mi (6,663.37 km) |
| West Allis to Ommen | 4,114.64 mi (6,621.87 km) |
| West Allis to Oosterend | 4,084.38 mi (6,573.18 km) |
| West Allis to Oosterhout | 4,090.47 mi (6,582.97 km) |
| West Allis to Oosterwolde | 4,092.81 mi (6,586.75 km) |
| West Allis to Oostzaan | 4,062.84 mi (6,538.51 km) |
| West Allis to Opmeer | 4,055.65 mi (6,526.94 km) |
| West Allis to Oss | 4,109.93 mi (6,614.29 km) |
| West Allis to Oud-Beijerland | 4,067.53 mi (6,546.05 km) |
| West Allis to Oudenbosch | 4,080.26 mi (6,566.55 km) |
