| Fort Hood to Olympia Heights (Florida) | 1,122.38 mi (1,806.30 km) |
| Fort Hood to Omaha (Nebraska) | 706.28 mi (1,136.65 km) |
| Fort Hood to On Top of the World Designated Place (Florida) | 935.90 mi (1,506.19 km) |
| Fort Hood to Onalaska (Wisconsin) | 951.17 mi (1,530.76 km) |
| Fort Hood to Oneida (New York) | 1,464.62 mi (2,357.08 km) |
| Fort Hood to Oneonta (New York) | 1,473.14 mi (2,370.79 km) |
| Fort Hood to Ontario (California) | 1,169.39 mi (1,881.96 km) |
| Fort Hood to Ontario (Oregon) | 1,371.42 mi (2,207.08 km) |
| Fort Hood to Opa-locka (Florida) | 1,122.40 mi (1,806.32 km) |
| Fort Hood to Opelika (Alabama) | 734.91 mi (1,182.72 km) |
| Fort Hood to Opelousas (Louisiana) | 340.87 mi (548.57 km) |
| Fort Hood to Orange (California) | 1,180.60 mi (1,899.99 km) |
| Fort Hood to Orange (Texas) | 249.18 mi (401.01 km) |
| Fort Hood to Orange City (Florida) | 997.35 mi (1,605.08 km) |
| Fort Hood to Orangeburg (South Carolina) | 999.96 mi (1,609.27 km) |
