Named after President Herbert Hoover, this grand reservoir was constructed over a span of five years during the Great Depression. Built to contain the roaring tempest of the mighty Colorado River, the Hoover Dam harnesses hydroelectric energy to feed the power-related needs of both California and the Southwest. Such is the magnificence of the dam that, energy harnessed from this massive marvel supplies electricity to over 20 million people. The dam spans an expanse of nearly 1250 feet (381 meters) over the Black Canyon gorge, and is located at the cusp of the Arizona-Nevada border. A prolific engineering spectacle that invites wonder and awe even decades after its construction, the colossal Hoover Dam remains one of the most remarkable accomplishments in architectural history.