Hoover Dam the change, stating, "I didn't know Hoover was that small a man to take credit for something he had nothing to do with." Hoover Dam was recognized as a National Civil Engineering Landmark in 1984. It was listed on the National Register of Historic Places in 1981, and was designated a National Historic Landmark in 1985, cited for its engineering innovations. Other sources Hoover Dam Hoover Dam is a concrete arch-gravity dam in the Black Canyon of the Colorado River, on the border between the U.S. states of Nevada and Arizona. It was constructed between 1931 and 1936 during the
Colorado City, Nevada Nevada. In 1866, Colorado City became the site of two stamp mills, located there for ease of supplying wood to operate its steam driven mechanism. One was the old Colorado Mill brought down the canyon from El Dorado City, and refurbished. The other was the new New Era Mill. The site of Colorado City, and the Colorado River it was adjacent to, was submerged under Lake Mohave following the construction of the Davis Dam in 1951. What remains of Colorado City lies offshore from the site of Nelson's Landing. Colorado City, Nevada Colorado City is now a ghost town, in