For no particular reason the speed limit changes from 65 to 55 and then there is a rise, on a curve. As you top the rise there lurks the deputy with his radar gun. By the time you can stop, there is a sign in view that says 65 mph. It’s a natural trap they’ve zoned slower. If you’re going to Arlington or FT. Worth take I45 and I20. But watch out because Ennis has a pice of I45 as well. In fact, North of Corsicana, stay under the limits (60, 65) all the way to Dallas. Down Houston way, the limit’s 75 and they don’t much play "Gotcha" with it..