| Silver Spring to Oskaloosa (Iowa) | 838.75 mi (1,349.84 km) |
| Silver Spring to Oswego (Illinois) | 623.51 mi (1,003.44 km) |
| Silver Spring to Oswego (New York) | 308.57 mi (496.59 km) |
| Silver Spring to Otsego (Minnesota) | 951.77 mi (1,531.73 km) |
| Silver Spring to Ottawa (Illinois) | 643.47 mi (1,035.57 km) |
| Silver Spring to Ottawa (Kansas) | 981.06 mi (1,578.86 km) |
| Silver Spring to Ottumwa (Iowa) | 825.55 mi (1,328.60 km) |
| Silver Spring to Overland (Missouri) | 717.93 mi (1,155.39 km) |
| Silver Spring to Overland Park (Kansas) | 947.88 mi (1,525.47 km) |
| Silver Spring to Overlea (Maryland) | 36.74 mi (59.13 km) |
| Silver Spring to Oviedo (Florida) | 753.45 mi (1,212.56 km) |
| Silver Spring to Owasso (Oklahoma) | 1,044.08 mi (1,680.28 km) |
| Silver Spring to Owatonna (Minnesota) | 907.00 mi (1,459.67 km) |
| Silver Spring to Owensboro (Kentucky) | 553.28 mi (890.42 km) |
| Silver Spring to Owings Mills (Maryland) | 30.79 mi (49.56 km) |
