| Cahokia to Orangevale (California) | 1,667.46 mi (2,683.52 km) |
| Cahokia to Orchards (Washington) | 1,716.12 mi (2,761.84 km) |
| Cahokia to Orcutt (California) | 1,686.60 mi (2,714.32 km) |
| Cahokia to Oregon (Ohio) | 415.30 mi (668.36 km) |
| Cahokia to Oregon (Wisconsin) | 304.09 mi (489.38 km) |
| Cahokia to Oregon City (Oregon) | 1,717.15 mi (2,763.49 km) |
| Cahokia to Orem (Utah) | 1,151.82 mi (1,853.67 km) |
| Cahokia to Orinda (California) | 1,728.77 mi (2,782.19 km) |
| Cahokia to Orland Park (Illinois) | 243.28 mi (391.52 km) |
| Cahokia to Orlando (Florida) | 862.27 mi (1,387.69 km) |
| Cahokia to Ormond Beach (Florida) | 824.12 mi (1,326.30 km) |
| Cahokia to Oro Valley (Arizona) | 1,241.21 mi (1,997.53 km) |
| Cahokia to Oroville (California) | 1,677.11 mi (2,699.05 km) |
| Cahokia to Oshkosh (Wisconsin) | 386.30 mi (621.69 km) |
| Cahokia to Oskaloosa (Iowa) | 229.13 mi (368.74 km) |
