Centerville, tx is roughly the half way point.
The halfway point between Dallas, Texas and Warren, Ohio is in Centerville, Tennessee.
A rough estimate would be Amarillo, Texas.
TENNESEE
denver Colorado
Four Corners, USA
Panama city,fl
The halfway point between Phoenix, Arizona and Dallas, Texas is Eagle Flat, Texas.
The town between Longview and Dallas on I-20 is Canton. It's in Texas.
hwy 71 and I10 west is a good halfway point, if you are traveling I10. Going 290, it would be where the Interstate makes a 90 degree turn (Im not sure of the town).
The distance between Cypress, Texas and Houston, Texas is approximately 30 miles.
Hewitt, Texas
Waco is located in central Texas about halfway between Dallas and Austin.