1936. The Hoover Dam was completed ahead of schedule in 1936. It was the first and most important link in a chain of dams, canals and aqueducts built to harness the Colorado River. The colossal mass of concrete is wedged into Black Canyon on the Arizona-Nevada border, 32 miles southeast of Las Vegas, and still inspires awe in the more than 1 million people who visit it each year.
