| Romeoville to Orangeburg (South Carolina) | 687.27 mi (1,106.06 km) |
| Romeoville to Orangevale (California) | 1,749.89 mi (2,816.17 km) |
| Romeoville to Orchards (Washington) | 1,730.00 mi (2,784.16 km) |
| Romeoville to Orcutt (California) | 1,803.38 mi (2,902.26 km) |
| Romeoville to Oregon (Ohio) | 240.98 mi (387.82 km) |
| Romeoville to Oregon (Wisconsin) | 111.05 mi (178.72 km) |
| Romeoville to Oregon City (Oregon) | 1,734.45 mi (2,791.32 km) |
| Romeoville to Orem (Utah) | 1,230.86 mi (1,980.88 km) |
| Romeoville to Orinda (California) | 1,816.64 mi (2,923.61 km) |
| Romeoville to Orland Park (Illinois) | 12.40 mi (19.95 km) |
| Romeoville to Orlando (Florida) | 985.26 mi (1,585.62 km) |
| Romeoville to Ormond Beach (Florida) | 937.91 mi (1,509.42 km) |
| Romeoville to Oro Valley (Arizona) | 1,407.28 mi (2,264.80 km) |
| Romeoville to Oroville (California) | 1,751.55 mi (2,818.85 km) |
| Romeoville to Oshkosh (Wisconsin) | 166.85 mi (268.51 km) |
