Get to a very identifiable feature like a lake so you can pinpoint your location then start finding the nearby peaks and ridges on the map. The go to the top of a hill/ Mtn and look down matching features.
Not very familiar with Texas topography are you?
The area around me is dead flat for 70 miles to the south, 200 miles to the north and east, and 800 miles to the west.
My choices are flat prairie or flat pine forest forest.
-Blast