Wow! I had no idea how important the Hoover Dam is to US history. It gave thousands of people (men) jobs during the Great Depression and acted as a symbol of "look what the US is capable of doing." It amazes me that they completed it two years early (why can't contractors do that on a regular basis when it was done on such a huge project?!). The size of it was impressive. The scope of it is hard to fathom. The amount of concrete it took to build it is crazy! I had mixed feelings about the impact of the Hoover Dam on our culture (allowing greater development of massive cities and destruction of the environment resulting from it and it's "benefits"), but they lessened a bit after the tour. I still do wonder how development would have been limited had it not been built... would that be a better thing or a worse thing? I suppose we will never know. But if you come this way, you must do the tour. Oh, and I was surprised at the cost: $30/person plus $10 for parking. I've been used to free or cheaper tours, so this was a surprise. But it was worth it nonetheless.