Access Restricted Archival objects in this container: Postcard: Hoover Dam construction of diversion tunnel 1, approximately 1930-1935 Postcard: Hoover Dam construction of diversion tunnel 2 with concrete, approximately 1930-1935 Postcard: Hoover Dam construction of diversion tunnel 3, approximately 1930-1935 Postcard: Hoover Dam construction of diversion tunnel, approximately 1930-1935 Postcard: concrete truck at Hoover Dam, approximately 1930-1935 Postcard: visitors' corridor at Hoover Dam, approximately 1930-1935 Postcard: visitors' corridor in Hoover Dam, approximately 1930-1935 Postcard: power generators in Hoover Dam, approximately 1930-1935 Postcard: power generators in Hoover Dam, approximately 1930-1935 Postcard: power house at Hoover Dam, approximately 1930-1935 Postcard: Winged Figures of the Republic at Hoover Dam, approximately 1930-1935 Postcard: Hoover Dam, approximately 1930-1935 Postcard: Hoover Dam, approximately 1935-1960 Postcard: Hoover Dam, approximately 1935-1960 Postcard: Hoover Dam, approximately 1935-1960 Postcard: Hoover Dam, approximately 1935-1960 Postcard: Hoover Dam, approximately 1935-1960 Postcard: Hoover Dam, approximately 1935-1960 Postcard: Hoover Dam, approximately 1935-1960 Postcard: Hoover Dam, approximately 1935-1960 Postcard: Hoover Dam, approximately 1935-1960 Postcard: Hoover Dam, approximately 1935-1960 Postcard: Hoover Dam, approximately 1935-1960 Postcard: Hoover Dam, approximately 1935-1960 Postcard: Hoover Dam, approximately 1935-1960