Get a tour bus to take you from Las Vegas or better yet drive yourself. It's about an hour drive from downtown Vegas. Beautiful views of the lake and surrounding area. Park for free on the AZ side up the hill from the spill over if you don't mind walking a little. Otherwise, pay 10 dollars for parking. I recommend walking over the memorial bridge as well. It offers spectacular views of the dam and lake. Tours are offered once you get to the dam if you want to pay to go behind the scenes to see how it all works (I recommend it's supper interesting) otherwise free to walk around the top of the dam.