U.S. HOOVER DAM CONSTRUCTION

This aerial view shows a crest of the Hoover Dam, aka Boulder Dam, showing the highway leading across it on July 16, 1935. The road, soon to be opened to the public, will provide an easy route between Las Vegas, Nev., and Kingman, Arizona. The intake towers jut up on the other side of the dam in Boulder City, Nevada. (AP Photo)