On July 7, 1930, construction of the Hoover Dam begins. Over the next five years, a total of 21,000 men would work ceaselessly to produce what would be the largest dam of its time, as well as one of the largest manmade structures in the world.

Although the dam would take only five years to build, its construction was nearly 30 years in the making. Arthur Powell Davis, an engineer from the Bureau of Reclamation, originally had his vision for the Hoover Dam back in 1902, and his engineering report on the topic became the guiding document when plans were finally made to begin the dam in 1922.

Source: Construction on Hoover Dam Begins – HISTORY

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