Postcard with an illustration of Colorado River looking upstream between mountains. The typed caption reads: "Colorado River, looking upstream, Boulder Damsite in 1931."
Postcard with an illustration of men working by the entrance a diversion tunnel. The caption reads: "Entrance to of one of the four 56 foot diversion tunnels."
Illustration on a postcard of giant tunnels creating diversions for the Colorado River during the construction of Hoover Dam. The caption reads: "Diverting the Colorado River through giant tunnels."
Illustration of Boulder Dam, later called Hoover Dam, construction. Caption reads: "A close-up, showing construction detail, Boulder Dam, Colorado River."
Guest house and main building of Scotty's Castle. The National Park Service bought the private property in 1970 and it is now a part of Death Valley National Park. Site Name: Scotty's Castle (Death Valley, Calif.)
Postcard of watchtower at Scotty's Castle. Scotty's Castle was bought by National Park Service in 1970 and it is now a property of Death Valley National Park.