As if the Hoover Dam isn't enough of an engineering marvel, the new bypass bridge soaring over the Colorado River is the longest bridge built with concrete arches in the western hemisphere.

The 1,900-foot engineering wonder perched 890 feet above the Colorado River is expected to drastically cut travel time along the main route between Las Vegas and Phoenix, as motorists will no longer have to make their way across the dam's winding two-lane road at a snail's pace.