American Scientist

Late last winter, publications ranging from Civil Engineering to the New York Times ran stories describing a spectacular new man-made structure designed to jut out about 70 feet from a wall of the Grand Canyon and sit almost 4,000 feet above the level of the Colorado River. This marvel of engineering is officially named The Skywalk, and it has been described variously as a "glass cantilever-designed bridge" and a "cantilevered glass semicircular walkway." In fact, its principal structural material is steel, but its glass floor and parapet walls enable visitors to get a "720-degree view" of the canyon, which means 360 degrees vertically plus 360 degrees horizontally. The cantilever principle that makes such an achievement possible is ubiquitous.