There are
1,480 mi
from Rockville, MD to Harker Heights, TX
That's the driving distance. It would take 1 day 2 hours to go from Rockville, Maryland to Harker Heights, Texas.
The flight distance (direct flight from Rockville, MD to Harker Heights, TX) is 1,280.51 mi.
1,480 mi = 2,381.82 kms