| Middle River to Oswego (Illinois) | 645.66 mi (1,039.10 km) |
| Middle River to Oswego (New York) | 283.86 mi (456.83 km) |
| Middle River to Otsego (Minnesota) | 966.66 mi (1,555.69 km) |
| Middle River to Ottawa (Illinois) | 666.99 mi (1,073.41 km) |
| Middle River to Ottawa (Kansas) | 1,011.41 mi (1,627.71 km) |
| Middle River to Ottumwa (Iowa) | 850.92 mi (1,369.43 km) |
| Middle River to Overland (Missouri) | 749.09 mi (1,205.54 km) |
| Middle River to Overland Park (Kansas) | 977.82 mi (1,573.64 km) |
| Middle River to Overlea (Maryland) | 5.13 mi (8.25 km) |
| Middle River to Oviedo (Florida) | 786.74 mi (1,266.14 km) |
| Middle River to Owasso (Oklahoma) | 1,077.84 mi (1,734.61 km) |
| Middle River to Owatonna (Minnesota) | 924.66 mi (1,488.10 km) |
| Middle River to Owensboro (Kentucky) | 587.67 mi (945.76 km) |
| Middle River to Owings Mills (Maryland) | 20.10 mi (32.35 km) |
| Middle River to Owosso (Michigan) | 475.27 mi (764.88 km) |
