| Severn to Oskaloosa (Iowa) | 853.11 mi (1,372.95 km) |
| Severn to Oswego (Illinois) | 636.68 mi (1,024.64 km) |
| Severn to Oswego (New York) | 298.39 mi (480.20 km) |
| Severn to Otsego (Minnesota) | 961.71 mi (1,547.71 km) |
| Severn to Ottawa (Illinois) | 657.26 mi (1,057.75 km) |
| Severn to Ottawa (Kansas) | 997.83 mi (1,605.85 km) |
| Severn to Ottumwa (Iowa) | 840.19 mi (1,352.16 km) |
| Severn to Overland (Missouri) | 735.00 mi (1,182.86 km) |
| Severn to Overland Park (Kansas) | 964.47 mi (1,552.17 km) |
| Severn to Overlea (Maryland) | 18.45 mi (29.70 km) |
| Severn to Oviedo (Florida) | 768.10 mi (1,236.14 km) |
| Severn to Owasso (Oklahoma) | 1,062.19 mi (1,709.43 km) |
| Severn to Owatonna (Minnesota) | 918.20 mi (1,477.70 km) |
| Severn to Owensboro (Kentucky) | 571.59 mi (919.89 km) |
| Severn to Owings Mills (Maryland) | 19.74 mi (31.78 km) |
