Black and white aerial view of Black Canyon at Hoover Dam construction site. There are four visible bridges going over the Colorado River. Note: Boulder Dam was officially renamed Hoover Dam in 1947.
Black and white image showing a downstream view of the Hoover Dam construction site from the lower slope of the upper cofferdam. The excavation for the base of the Nevada intake towers can be seen in the upper right. Note: Boulder Dam was officially renamed Hoover Dam in 1947.