| Festus to Oswego (Illinois) | 263.29 mi (423.72 km) |
| Festus to Oswego (New York) | 810.60 mi (1,304.53 km) |
| Festus to Otsego (Minnesota) | 514.12 mi (827.39 km) |
| Festus to Ottawa (Illinois) | 232.41 mi (374.03 km) |
| Festus to Ottawa (Kansas) | 264.07 mi (424.98 km) |
| Festus to Ottumwa (Iowa) | 221.03 mi (355.71 km) |
| Festus to Overland (Missouri) | 33.05 mi (53.18 km) |
| Festus to Overland Park (Kansas) | 235.65 mi (379.24 km) |
| Festus to Overlea (Maryland) | 751.56 mi (1,209.51 km) |
| Festus to Oviedo (Florida) | 847.04 mi (1,363.18 km) |
| Festus to Owasso (Oklahoma) | 326.59 mi (525.59 km) |
| Festus to Owatonna (Minnesota) | 431.36 mi (694.21 km) |
| Festus to Owensboro (Kentucky) | 182.10 mi (293.06 km) |
| Festus to Owings Mills (Maryland) | 737.05 mi (1,186.17 km) |
| Festus to Owosso (Michigan) | 464.30 mi (747.22 km) |
