Transported (8) 16' long deck boards.
My son says it feels like driving a tank from inside (even more so when it's a big pipe).
Sorry it's blurry I just zoomed in on the first photo: I have some 2x3 bolted down to my roof rack from moving a 70x50 inch window recently. Came in super handy today : I just screwed the first two boards down flat and then screwed the rest vertically to the previous board.
If I go a long distance I have steel angles I will bolt on to hold the 2x6 etc upright and I'll pound a shim in to make them amazingly tight.
A 3 hr drive is nothing with 4-5 12' 2x6.