| Oak Forest to Oswego (Illinois) | 30.66 mi (49.34 km) |
| Oak Forest to Oswego (New York) | 586.47 mi (943.83 km) |
| Oak Forest to Otsego (Minnesota) | 387.92 mi (624.30 km) |
| Oak Forest to Ottawa (Illinois) | 58.18 mi (93.64 km) |
| Oak Forest to Ottawa (Kansas) | 447.76 mi (720.60 km) |
| Oak Forest to Ottumwa (Iowa) | 245.48 mi (395.06 km) |
| Oak Forest to Overland (Missouri) | 243.86 mi (392.45 km) |
| Oak Forest to Overland Park (Kansas) | 410.93 mi (661.33 km) |
| Oak Forest to Overlea (Maryland) | 609.89 mi (981.52 km) |
| Oak Forest to Oviedo (Florida) | 967.68 mi (1,557.32 km) |
| Oak Forest to Owasso (Oklahoma) | 568.25 mi (914.51 km) |
| Oak Forest to Owatonna (Minnesota) | 326.26 mi (525.07 km) |
| Oak Forest to Owensboro (Kentucky) | 268.00 mi (431.31 km) |
| Oak Forest to Owings Mills (Maryland) | 594.98 mi (957.52 km) |
| Oak Forest to Owosso (Michigan) | 206.45 mi (332.26 km) |
