| Castricum to Oswego (Illinois) | 4,126.62 mi (6,641.15 km) |
| Castricum to Oswego (New York) | 3,602.35 mi (5,797.42 km) |
| Castricum to Otsego (Minnesota) | 4,135.17 mi (6,654.92 km) |
| Castricum to Ottawa (Illinois) | 4,160.51 mi (6,695.69 km) |
| Castricum to Ottawa (Kansas) | 4,531.53 mi (7,292.79 km) |
| Castricum to Ottumwa (Iowa) | 4,306.27 mi (6,930.27 km) |
| Castricum to Overland (Missouri) | 4,349.82 mi (7,000.37 km) |
| Castricum to Overland Park (Kansas) | 4,496.11 mi (7,235.79 km) |
| Castricum to Overlea (Maryland) | 3,790.50 mi (6,100.21 km) |
| Castricum to Oviedo (Florida) | 4,505.51 mi (7,250.91 km) |
| Castricum to Owasso (Oklahoma) | 4,672.93 mi (7,520.35 km) |
| Castricum to Owatonna (Minnesota) | 4,180.36 mi (6,727.64 km) |
| Castricum to Owensboro (Kentucky) | 4,276.27 mi (6,882.00 km) |
| Castricum to Owings Mills (Maryland) | 3,799.02 mi (6,113.93 km) |
| Castricum to Owosso (Michigan) | 3,911.23 mi (6,294.52 km) |
