| Westerlo to Oswego (Illinois) | 4,187.56 mi (6,739.23 km) |
| Westerlo to Oswego (New York) | 3,655.26 mi (5,882.57 km) |
| Westerlo to Otsego (Minnesota) | 4,204.37 mi (6,766.28 km) |
| Westerlo to Ottawa (Illinois) | 4,221.49 mi (6,793.84 km) |
| Westerlo to Ottawa (Kansas) | 4,595.18 mi (7,395.23 km) |
| Westerlo to Ottumwa (Iowa) | 4,369.97 mi (7,032.78 km) |
| Westerlo to Overland (Missouri) | 4,409.17 mi (7,095.87 km) |
| Westerlo to Overland Park (Kansas) | 4,559.54 mi (7,337.87 km) |
| Westerlo to Overlea (Maryland) | 3,837.49 mi (6,175.84 km) |
| Westerlo to Oviedo (Florida) | 4,543.41 mi (7,311.92 km) |
| Westerlo to Owasso (Oklahoma) | 4,734.77 mi (7,619.87 km) |
| Westerlo to Owatonna (Minnesota) | 4,248.02 mi (6,836.52 km) |
| Westerlo to Owensboro (Kentucky) | 4,331.50 mi (6,970.87 km) |
| Westerlo to Owings Mills (Maryland) | 3,846.35 mi (6,190.10 km) |
| Westerlo to Owosso (Michigan) | 3,970.20 mi (6,389.43 km) |
