| Pikesville to Oskaloosa (Iowa) | 848.36 mi (1,365.30 km) |
| Pikesville to Oswego (Illinois) | 630.64 mi (1,014.92 km) |
| Pikesville to Oswego (New York) | 280.87 mi (452.02 km) |
| Pikesville to Otsego (Minnesota) | 952.34 mi (1,532.64 km) |
| Pikesville to Ottawa (Illinois) | 651.91 mi (1,049.15 km) |
| Pikesville to Ottawa (Kansas) | 996.49 mi (1,603.70 km) |
| Pikesville to Ottumwa (Iowa) | 835.81 mi (1,345.11 km) |
| Pikesville to Overland (Missouri) | 734.26 mi (1,181.68 km) |
| Pikesville to Overland Park (Kansas) | 962.86 mi (1,549.57 km) |
| Pikesville to Overlea (Maryland) | 10.01 mi (16.10 km) |
| Pikesville to Oviedo (Florida) | 784.39 mi (1,262.35 km) |
| Pikesville to Owasso (Oklahoma) | 1,063.42 mi (1,711.40 km) |
| Pikesville to Owatonna (Minnesota) | 910.01 mi (1,464.51 km) |
| Pikesville to Owensboro (Kentucky) | 573.44 mi (922.87 km) |
| Pikesville to Owings Mills (Maryland) | 5.01 mi (8.06 km) |
