How many miles from Oklahoma City Oklahoma to Midland Texas?

500 miles taking this route:

1. Take I-35 SOUTH, from Oklahoma City, to I-35W SOUTH to FT. WORTH in Texas; continue on I-35W SOUTH to I-820 WEST off EXIT 57B.
2. Take I-820, around Ft. Worth, to I-20 WEST to ABILENE off EXIT 1.
3. Take I-20 WEST to Midland.