The Kinzua Bridge was once the longest and tallest railroad bridge in the world, measuring 2,053 ft. long and 301 ft. high.  In 2003, a tornado destroyed the majority of the bridge.  In 2011, the remaining portion was converted into a pedestrian walkway which stretches 600 ft. out over the Kinzua Gorge with views for miles around.  The floor at the end of the skywalk is made of glass, allowing the bold and daring to look 300 ft. straight down past their feet into the valley below. This is a must visit destination if you are in the Allegheny National Forest.