Boulder Dam, now known as Hoover Dam, is a concrete arch-gravity dam located on the Colorado River between Nevada and Arizona. Completed in 1936, it was built during the Great Depression to provide jobs and stabilize the economy. The dam is 726 feet tall and 1,244 feet long, creating Lake Mead, one of the largest artificial lakes in the United States. The primary purpose of Hoover Dam is to control flooding, provide irrigation water, and generate hydroelectric power. It produces about 4 billion kilowatt-hours of electricity annually, supplying power to millions of people in the surrounding states. The dam is also a popular tourist destination, attracting visitors with its impressive engineering and scenic views.