Access Restricted Archival objects in this container: Hoover Dam construction, approximately 1930-1935 Hoover Dam construction machinery, 1931 June 01 Hoover Dam construction camp, approximately 1930-1935 Hoover Dam construction buses, approximately 1930-1935 Postcard: trains near the Hoover Dam site, approximately 1930-1935 Workers on truck for Hoover Dam construction, approximately 1930-1935 Truck near Colorado River, approximately 1925-1935 Workers using bulldozer, Hoover Dam construction, approximately 1925-1935 Tunnel during construction of Hoover Dam, approximately 1920-1930 Hoover Dam dedication, 1935 September 30 Nevada-California Electric Corporation sign, 1935 Hoover Dam power plant, 1935 Hoover Dam, approximately 1930-1940 Postcard: Union Pacific Railroad train during Hoover Dam construction, approximately 1925-1935 Postcard: Colorado River, approximately 1925-1935 Postcard: Colorado River, approximately 1925-1935 Postcard: Black Canyon, approximately 1925-1935 Postcard: Hoover Dam during construction, approximately 1925-1935 Postcard: Hoover Dam at night, approximately 1935 Postcard: Hoover Dam at night, approximately 1935 Postcard: Hoover Dam at night, approximately 1935 Postcard: Cape Horn explosion during construction of Hoover Dam, approximately 1930-1935 Postcard: gravel grading plant during Hoover Dam construction, approximately 1930-1935 Postcard: Hoover Dam construction, approximately 1930-1935 Postcard: Hoover Dam tunnels, approximately 1930-1935