| West Chicago to Nuth | 4,215.06 mi (6,783.48 km) |
| West Chicago to Oegstgeest | 4,117.68 mi (6,626.76 km) |
| West Chicago to Oirschot | 4,172.43 mi (6,714.88 km) |
| West Chicago to Oisterwijk | 4,165.77 mi (6,704.17 km) |
| West Chicago to Oldebroek | 4,160.23 mi (6,695.24 km) |
| West Chicago to Oldenzaal | 4,202.19 mi (6,762.76 km) |
| West Chicago to Ommen | 4,176.40 mi (6,721.27 km) |
| West Chicago to Oosterend | 4,146.43 mi (6,673.03 km) |
| West Chicago to Oosterhout | 4,151.03 mi (6,680.44 km) |
| West Chicago to Oosterwolde | 4,154.92 mi (6,686.69 km) |
| West Chicago to Oostzaan | 4,124.07 mi (6,637.05 km) |
| West Chicago to Opmeer | 4,117.12 mi (6,625.87 km) |
| West Chicago to Oss | 4,170.80 mi (6,712.26 km) |
| West Chicago to Oud-Beijerland | 4,128.10 mi (6,643.53 km) |
| West Chicago to Oudenbosch | 4,140.68 mi (6,663.78 km) |
