The Hoover Dam has been called one of America’s Modern Civil Engineering Wonders of the World! While at the dam, you will go on the Hoover Dam Powerplant tour, view the Arizona Spillway and Look Out. The Look Out provides a spectacular view of the entire Hoover Dam complex. Construction of the dam took less than five years and was completed in 1935. At that time, it was both the world’s largest electric power producing facility and the world’s largest concrete structure. An unlimited amount of bottled water is included with this tour.