| Castricum to Odessa (Texas) | 5,143.41 mi (8,277.52 km) |
| Castricum to Ogden (Utah) | 4,936.46 mi (7,944.46 km) |
| Castricum to Oildale (California) | 5,480.49 mi (8,819.99 km) |
| Castricum to Ojus (Florida) | 4,603.27 mi (7,408.25 km) |
| Castricum to Okemos (Michigan) | 3,933.73 mi (6,330.72 km) |
| Castricum to Oklahoma City (Oklahoma) | 4,776.81 mi (7,687.54 km) |
| Castricum to Okmulgee (Oklahoma) | 4,714.87 mi (7,587.86 km) |
| Castricum to Olathe (Kansas) | 4,501.03 mi (7,243.71 km) |
| Castricum to Old Jamestown (Missouri) | 4,339.51 mi (6,983.76 km) |
| Castricum to Oldsmar (Florida) | 4,596.80 mi (7,397.84 km) |
| Castricum to Olean (New York) | 3,738.39 mi (6,016.35 km) |
| Castricum to Olive Branch (Mississippi) | 4,521.26 mi (7,276.26 km) |
| Castricum to Olivehurst (California) | 5,334.09 mi (8,584.39 km) |
| Castricum to Olney (Maryland) | 3,822.46 mi (6,151.65 km) |
| Castricum to Olympia (Washington) | 4,893.81 mi (7,875.83 km) |
