The Boulder City 31ers Photograph Collection depicts the construction of the Hoover (Boulder) Dam and the development of Boulder City, Nevada from 1930 to 1987. The photographs primarily depict construction of the Hoover Dam, but they also depict workers, dormitories, the Colorado River, stores, and Black Canyon.
Transcribed from back of photo: "Howard Hughes (in cockpit) warms up the XF-11 for its initial test flight. It is one of the world's fastest long-range photographic planes, July 7, 1946."