I've walked across the Royal Gorge Bridge in Colorado, and ridden in a car across the Mackinac Bridge in Michigan (I wasn't behind the wheel, though). I loved the Mackinac Bridge visually but didn't think it was any big deal going across it. The Royal Gorge Bridge was something of a thrill not only because of how high up above the canyon you were, but also because the old wooden planks gave way under your feet some when you walked across it, and gave way even more if a car happened to drive across while you were walking. I also think it swayed a little, but don't remember for sure.The scariest bridge I ever walked across was the Clark Avenue Bridge in Cleveland before they tore it down. It was a long, long span that cut right through the steel mills to connect the east and west sides of town. It had been so eaten up and eroded by the industrial fumes in the air that there were portions of bridge railings missing and holes in the sidewalk that you could look clear through. Technically, the sidewalk was closed when I walked across the bridge, but as a daring teenager I did it anyway.