Materials contain photographic prints, photographic slides, and photographic negatives depicting the Hoover (Boulder) Dam from 1930 to 1959. The photographs primarily depict the completed dam, including its upstream and downstream faces, diversion tunnels, outlet works, powerhouse, intake towers, crest, and spillways. The photographs depict the dam from numerous angles, including photographs taken from both the Nevada and Arizona sides of the dam, the Colorado River, Lake Mead, and aerial photographs taken from planes.