Hoover Dam

The concrete colossus that tamed the Colorado River/Everyday Places

Built during the Great Depression between 1931 and 1936, the Hoover Dam was the largest concrete structure in the world at the time. It impounds Lake Mead, the largest reservoir in the United States by volume. The concrete in the dam would be enough to pave a two-lane highway from San Francisco to New York. It generates enough electricity to serve 1.3 million people, which is handy since Las Vegas is right there.