Hey Hoop....We've riden all the Sanderson /Pandale area and it is dirt county roads....Having said that I'll go back there any time it is just great riding.
We ride from Ozona, down thru Pandale and into Sanderson, about 60% dirt. From Sanderson we ride pavement to Big Bend Park where we pick up the dirt again into Terlingua Ranch. From the ranch there are dirt roads all the way to Lajitas and over 170 miles in the National Park.
I forgot to mention the 1100 plus miles of dirt roads on the ranch.

I would not like to do any of it on a big BMW, but it's perfect for all D/S 400's and 650's. Experienced KLR riders would love it too.

Stay tuned we'll work up a trip early in the new year.

Steve Smith