So much greenery

Almost from the moment we drove east of the Mississippi, amidst the kids' choruses of spelling the river's name forwards and backwards, our easterly route along our friend I-40 entered one massive corridor of greenery, extending for miles and miles and interrupted every hundred miles or so by the larger cities. It became almost claustrophobic to cruise through this mass of foliage with very little in the way of a visual break. Trees on either side of the highway, many of them choked by prolific strands of ivy, rose like two walls on both sides making it impossible to tell what the countryside offered on the other side. Or was there another side? Could the land all be like this? Would it ever open up to reveal its secrets?