| Slovenj Gradec to Orangevale (California) | 5,960.49 mi (9,592.48 km) |
| Slovenj Gradec to Orchards (Washington) | 5,566.03 mi (8,957.65 km) |
| Slovenj Gradec to Orcutt (California) | 6,170.88 mi (9,931.07 km) |
| Slovenj Gradec to Oregon (Ohio) | 4,563.11 mi (7,343.61 km) |
| Slovenj Gradec to Oregon (Wisconsin) | 4,725.76 mi (7,605.37 km) |
| Slovenj Gradec to Oregon City (Oregon) | 5,588.61 mi (8,994.00 km) |
| Slovenj Gradec to Orem (Utah) | 5,602.54 mi (9,016.41 km) |
| Slovenj Gradec to Orinda (California) | 6,034.19 mi (9,711.09 km) |
| Slovenj Gradec to Orland Park (Illinois) | 4,732.91 mi (7,616.89 km) |
| Slovenj Gradec to Orlando (Florida) | 5,101.87 mi (8,210.67 km) |
| Slovenj Gradec to Ormond Beach (Florida) | 5,051.95 mi (8,130.33 km) |
| Slovenj Gradec to Oro Valley (Arizona) | 6,032.19 mi (9,707.88 km) |
| Slovenj Gradec to Oroville (California) | 5,919.86 mi (9,527.10 km) |
| Slovenj Gradec to Oshkosh (Wisconsin) | 4,643.31 mi (7,472.69 km) |
| Slovenj Gradec to Oskaloosa (Iowa) | 4,923.22 mi (7,923.16 km) |
