A statue of bronze winged figures stands atop Hoover Dam, memorializing those who built the massive 726ft concrete structure, one of the world's tallest dams. Originally named Boulder Dam, this New Deal public works project, completed ahead of schedule and under budget in 1936, was the Colorado River's first major dam. Thousands of men and their families, eager for work in the height of the Depression, came to Black Canyon and worked in excruciating conditions – dangling hundreds of feet above the canyon in 120°F (about 50°C) desert heat. Hundreds lost their lives.

Today, guided tours begin at the visitor center, where a video screening features original footage of the construction. Then take an elevator ride 50 stories below to view the dam's massive power generators, each of which alone could power a city of 100,000 people. Parking at the site costs $7.