Throughout the course of a day, workers dumped rocks into the river's path. By the next morning, they moved the Colorado River from the bed it had known for 12 million years.
On June 6, 1933, workers poured the first bucket of concrete that would build the dam.
Building the 700 foot high dam was only one piece of the puzzle.
During the dam's construction, the job of the high scaler was by far the most dangerous.