| Castelli Calepio to Orangevale (California) | 5,869.94 mi (9,446.76 km) |
| Castelli Calepio to Orchards (Washington) | 5,493.97 mi (8,841.69 km) |
| Castelli Calepio to Orcutt (California) | 6,070.06 mi (9,768.81 km) |
| Castelli Calepio to Oregon (Ohio) | 4,393.84 mi (7,071.20 km) |
| Castelli Calepio to Oregon (Wisconsin) | 4,571.08 mi (7,356.44 km) |
| Castelli Calepio to Oregon City (Oregon) | 5,515.96 mi (8,877.09 km) |
| Castelli Calepio to Orem (Utah) | 5,490.17 mi (8,835.58 km) |
| Castelli Calepio to Orinda (California) | 5,944.68 mi (9,567.05 km) |
| Castelli Calepio to Orland Park (Illinois) | 4,571.64 mi (7,357.35 km) |
| Castelli Calepio to Orlando (Florida) | 4,897.14 mi (7,881.19 km) |
| Castelli Calepio to Ormond Beach (Florida) | 4,848.51 mi (7,802.92 km) |
| Castelli Calepio to Oro Valley (Arizona) | 5,899.95 mi (9,495.05 km) |
| Castelli Calepio to Oroville (California) | 5,831.99 mi (9,385.67 km) |
| Castelli Calepio to Oshkosh (Wisconsin) | 4,490.22 mi (7,226.31 km) |
| Castelli Calepio to Oskaloosa (Iowa) | 4,770.38 mi (7,677.19 km) |
