| Thornton to Orangevale (California) | 5,102.38 mi (8,211.48 km) |
| Thornton to Orchards (Washington) | 4,731.67 mi (7,614.88 km) |
| Thornton to Orcutt (California) | 5,301.79 mi (8,532.41 km) |
| Thornton to Oregon (Ohio) | 3,666.65 mi (5,900.91 km) |
| Thornton to Oregon (Wisconsin) | 3,826.63 mi (6,158.37 km) |
| Thornton to Oregon City (Oregon) | 4,753.40 mi (7,649.87 km) |
| Thornton to Orem (Utah) | 4,722.84 mi (7,600.68 km) |
| Thornton to Orinda (California) | 5,177.25 mi (8,331.98 km) |
| Thornton to Orland Park (Illinois) | 3,834.25 mi (6,170.63 km) |
| Thornton to Orlando (Florida) | 4,238.84 mi (6,821.75 km) |
| Thornton to Ormond Beach (Florida) | 4,186.95 mi (6,738.24 km) |
| Thornton to Oro Valley (Arizona) | 5,139.43 mi (8,271.11 km) |
| Thornton to Oroville (California) | 5,064.86 mi (8,151.10 km) |
| Thornton to Oshkosh (Wisconsin) | 3,744.23 mi (6,025.76 km) |
| Thornton to Oskaloosa (Iowa) | 4,024.18 mi (6,476.28 km) |
