| Harker Heights to Odessa (Texas) | 282.74 mi (455.02 km) |
| Harker Heights to Ogden (Utah) | 1,061.61 mi (1,708.50 km) |
| Harker Heights to Oildale (California) | 1,269.42 mi (2,042.93 km) |
| Harker Heights to Ojus (Florida) | 1,117.02 mi (1,797.66 km) |
| Harker Heights to Okemos (Michigan) | 1,084.73 mi (1,745.70 km) |
| Harker Heights to Oklahoma City (Oklahoma) | 304.82 mi (490.57 km) |
| Harker Heights to Okmulgee (Oklahoma) | 328.68 mi (528.95 km) |
| Harker Heights to Olathe (Kansas) | 563.80 mi (907.34 km) |
| Harker Heights to Old Jamestown (Missouri) | 679.79 mi (1,094.02 km) |
| Harker Heights to Oldsmar (Florida) | 922.90 mi (1,485.26 km) |
| Harker Heights to Olean (New York) | 1,305.27 mi (2,100.63 km) |
| Harker Heights to Olive Branch (Mississippi) | 525.93 mi (846.41 km) |
| Harker Heights to Olivehurst (California) | 1,455.85 mi (2,342.97 km) |
| Harker Heights to Olney (Maryland) | 1,286.23 mi (2,069.99 km) |
| Harker Heights to Olympia (Washington) | 1,734.39 mi (2,791.22 km) |
