Hoover Dam 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 Great Depression and was dedicated on September 30, 1935, by President Franklin D. Roosevelt. Its construction was the result of a massive effort involving thousands of workers, and cost over one hundred lives. Originally known as Boulder Dam from 1933, it was officially renamed Hoover Dam, for President Herbert Hoover, by a joint resolution of Congress in 1947. Since about 1900, the Black
The Exploration of the Colorado River and Its Canyons The Exploration of the Colorado River and Its Canyons The Exploration of the Colorado River and Its Canyons by John Wesley Powell is a classic of American exploration literature. It is about the Powell Geographic Expedition of 1869 which was the first trip down the Colorado River by boat, including the first trip through the Grand Canyon. Powell's first written accounts of his exploration appeared in the January, February and March 1875 editions of "Scribner’s Monthly" as "The Canons of the Colorado". The Smithsonian published it in book form in 1875 under title "Report of the Exploration of the Colorado