Hoover Dam, once known as Boulder Dam, is a concrete arch gravity dam in the Black Canyon of the Colorado River, on the border between the U.S. states of Arizona and Nevada 

 

Hoover Dam impounds Lake Mead, the largest reservoir in the United States by volume

Hoover dam is located near Boulder City,Nevada, a municipality originally constructed for workers on the construction project, about 30 miles (48 km) southeast of Las Vegas,Nevada 

Hoover dam's generators provide power for public and private utilities in Nevada, Arizona, and California

Hoover Dam is a major tourist attraction; nearly a million people tour the dam each year.

It was constructed between 1931 and 1936 during the Great Depression and was dedicated on September 30, 1935, by President Franklin D Roosevelt