| Rockwall to Oskaloosa (Iowa) | 615.16 mi (990.01 km) |
| Rockwall to Oswego (Illinois) | 750.93 mi (1,208.51 km) |
| Rockwall to Oswego (New York) | 1,299.29 mi (2,091.01 km) |
| Rockwall to Otsego (Minnesota) | 866.36 mi (1,394.27 km) |
| Rockwall to Ottawa (Illinois) | 717.46 mi (1,154.64 km) |
| Rockwall to Ottawa (Kansas) | 398.10 mi (640.68 km) |
| Rockwall to Ottumwa (Iowa) | 602.00 mi (968.83 km) |
| Rockwall to Overland (Missouri) | 524.23 mi (843.66 km) |
| Rockwall to Overland Park (Kansas) | 423.94 mi (682.27 km) |
| Rockwall to Overlea (Maryland) | 1,194.19 mi (1,921.87 km) |
| Rockwall to Oviedo (Florida) | 950.74 mi (1,530.07 km) |
| Rockwall to Owasso (Oklahoma) | 235.44 mi (378.91 km) |
| Rockwall to Owatonna (Minnesota) | 791.12 mi (1,273.18 km) |
| Rockwall to Owensboro (Kentucky) | 622.26 mi (1,001.43 km) |
| Rockwall to Owings Mills (Maryland) | 1,181.03 mi (1,900.69 km) |
