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 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 of the Hoover Dam tunnel construction site. There are four visible bridges over the Colorado River. Note: Boulder Dam was officially renamed Hoover Dam in 1947.