| Alton to Oswego (Illinois) | 3,962.62 mi (6,377.22 km) |
| Alton to Oswego (New York) | 3,420.15 mi (5,504.20 km) |
| Alton to Otsego (Minnesota) | 3,993.59 mi (6,427.06 km) |
| Alton to Ottawa (Illinois) | 3,996.57 mi (6,431.86 km) |
| Alton to Ottawa (Kansas) | 4,374.04 mi (7,039.33 km) |
| Alton to Ottumwa (Iowa) | 4,149.15 mi (6,677.40 km) |
| Alton to Overland (Missouri) | 4,181.66 mi (6,729.73 km) |
| Alton to Overland Park (Kansas) | 4,338.08 mi (6,981.47 km) |
| Alton to Overlea (Maryland) | 3,595.97 mi (5,787.16 km) |
| Alton to Oviedo (Florida) | 4,294.48 mi (6,911.30 km) |
| Alton to Owasso (Oklahoma) | 4,510.63 mi (7,259.16 km) |
| Alton to Owatonna (Minnesota) | 4,034.23 mi (6,492.47 km) |
| Alton to Owensboro (Kentucky) | 4,098.57 mi (6,596.02 km) |
| Alton to Owings Mills (Maryland) | 3,605.15 mi (5,801.93 km) |
| Alton to Owosso (Michigan) | 3,742.61 mi (6,023.14 km) |
