| Castelli Calepio to Oakley (California) | 5,924.31 mi (9,534.25 km) |
| Castelli Calepio to Oakton (Virginia) | 4,257.24 mi (6,851.37 km) |
| Castelli Calepio to Oakville (Missouri) | 4,814.06 mi (7,747.48 km) |
| Castelli Calepio to Oatfield (Oregon) | 5,511.84 mi (8,870.46 km) |
| Castelli Calepio to Ocala (Florida) | 4,901.01 mi (7,887.41 km) |
| Castelli Calepio to Ocean Acres (New Jersey) | 4,092.50 mi (6,586.24 km) |
| Castelli Calepio to Ocean City (New Jersey) | 4,125.68 mi (6,639.65 km) |
| Castelli Calepio to Ocean Pines (Maryland) | 4,185.68 mi (6,736.20 km) |
| Castelli Calepio to Ocean Pointe (Hawaii) | 7,749.38 mi (12,471.43 km) |
| Castelli Calepio to Ocean Springs (Mississippi) | 5,132.95 mi (8,260.68 km) |
| Castelli Calepio to Oceanside (California) | 6,068.02 mi (9,765.53 km) |
| Castelli Calepio to Oceanside (New York) | 4,029.06 mi (6,484.15 km) |
| Castelli Calepio to Ocoee (Florida) | 4,901.20 mi (7,887.72 km) |
| Castelli Calepio to Oconomowoc (Wisconsin) | 4,529.00 mi (7,288.71 km) |
| Castelli Calepio to Odenton (Maryland) | 4,223.85 mi (6,797.63 km) |
