Hoover Dam was originally called Boulder Dam. Today, this dam is totally known as Hoover Dam; and, it is specifically 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. During the dedication ceremony, Roosevelt also referred to the dam as Boulder Dam. Years following the dedication the name Boulder Dam failed to fully take hold with the American public. Many Americans used both names interchangeably.

Its construction was the result of a massive effort involving thousands of workers, and it cost over one hundred lives. Since the dam was controversially named after President Herbert Hoover, a resolution naming the dam as Hoover Dam was passed by congress and signed by President Harry S. Truman in April 1947. Thus, Hoover Dam is now the official name of this structure.

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