| Castelli Calepio to Oswego (Illinois) | 4,586.77 mi (7,381.70 km) |
| Castelli Calepio to Oswego (New York) | 4,037.21 mi (6,497.26 km) |
| Castelli Calepio to Otsego (Minnesota) | 4,620.43 mi (7,435.87 km) |
| Castelli Calepio to Ottawa (Illinois) | 4,620.73 mi (7,436.34 km) |
| Castelli Calepio to Ottawa (Kansas) | 4,999.54 mi (8,045.98 km) |
| Castelli Calepio to Ottumwa (Iowa) | 4,774.80 mi (7,684.30 km) |
| Castelli Calepio to Overland (Missouri) | 4,804.33 mi (7,731.83 km) |
| Castelli Calepio to Overland Park (Kansas) | 4,963.49 mi (7,987.96 km) |
| Castelli Calepio to Overlea (Maryland) | 4,203.91 mi (6,765.53 km) |
| Castelli Calepio to Oviedo (Florida) | 4,882.02 mi (7,856.85 km) |
| Castelli Calepio to Owasso (Oklahoma) | 5,134.94 mi (8,263.89 km) |
| Castelli Calepio to Owatonna (Minnesota) | 4,661.07 mi (7,501.28 km) |
| Castelli Calepio to Owensboro (Kentucky) | 4,717.15 mi (7,591.52 km) |
| Castelli Calepio to Owings Mills (Maryland) | 4,213.62 mi (6,781.16 km) |
| Castelli Calepio to Owosso (Michigan) | 4,365.48 mi (7,025.55 km) |
