No fee to see a famous site - how can I resist? There's a lot of free parking, so don't pay the $10. Yes, the tour costs money, but it's free to walk along the dam and read the info signs. I wouldn't go out of my way to see this place, but if you're driving between Arizona and Nevada, it's worth driving a few extra minutes to see this place. I'm sure the tour would be interesting - I just didn't have time on this trip.