Black and white image of Hoover Dam with the following printed description: "Thirty-foot-diameter-steel-penstock pipe set up from joint assembly at the Babcock and Wilcox Co. Plant." Note: Boulder Dam was officially renamed Hoover Dam in 1947.
Black and white image of the Hoover Dam construction site at Black Canyon showing an upstream view during construction. This picture is one of several that cover the entire construction phase of the Hoover Dam from beginning on October 12, 1931, to completion on September 11, 1936. Note: Boulder Dam was officially renamed Hoover Dam in 1947.
An image from the power generator floor of visitors standing on a viewpoint platform inside the Hoover Dam powerhouse. Boulder Dam was officially renamed Hoover Dam in 1947.