Interesting topic for me , I vacation 5 to 6 times a summer , where I drive 400 miles over to wisconsin one way I usually work a double shift the sat. nite before I leave and get home at about 10:00 then pack the car and lay down for 4-5 hours and leave my driveway at about 4:00 , I eat well the day before , listen to soothing music , drink plenty of water and make frequent stops along the way to stretch and let the dog out and walk him [ he'll sleep all the way if I let him ] stretch , fresh air , wash windshield and check car over , get back in the drivers seat and repeat as necessary , the window is always open a bit , snack lightly and keep in mind the destination , After all that is why I do this . Enjoy the ride !!!