Illustration of Boulder Dam, later called Hoover Dam, with the view of lower portals and diversion tunnels. The caption reads: "Boulder Dam, looking upstream, showing Colorado River."
Looking upstream at the dam site, Hoover Dam, January 1933. Construction materials and small bridges line the canyon above the river as the dam is being built.
High scalers at Hoover Dam, with the Colorado River visible in the left side of the photo. Located on the back of the postcard is a handwritten description.