| Harker Heights to Oswego (Illinois) | 897.19 mi (1,443.88 km) |
| Harker Heights to Oswego (New York) | 1,437.15 mi (2,312.86 km) |
| Harker Heights to Otsego (Minnesota) | 1,005.43 mi (1,618.09 km) |
| Harker Heights to Ottawa (Illinois) | 863.79 mi (1,390.14 km) |
| Harker Heights to Ottawa (Kansas) | 538.28 mi (866.28 km) |
| Harker Heights to Ottumwa (Iowa) | 747.31 mi (1,202.68 km) |
| Harker Heights to Overland (Missouri) | 669.32 mi (1,077.17 km) |
| Harker Heights to Overland Park (Kansas) | 566.21 mi (911.23 km) |
| Harker Heights to Overlea (Maryland) | 1,319.18 mi (2,123.02 km) |
| Harker Heights to Oviedo (Florida) | 999.02 mi (1,607.77 km) |
| Harker Heights to Owasso (Oklahoma) | 376.12 mi (605.31 km) |
| Harker Heights to Owatonna (Minnesota) | 932.05 mi (1,499.98 km) |
| Harker Heights to Owensboro (Kentucky) | 757.06 mi (1,218.37 km) |
| Harker Heights to Owings Mills (Maryland) | 1,306.50 mi (2,102.60 km) |
| Harker Heights to Owosso (Michigan) | 1,107.25 mi (1,781.95 km) |
