Our first stop was something out of the movies- the Hoover Dam (originally Boulder Dam)
Built from 1931 to 1936 its quite the amazing feat of construction. I don't really get how they did it but I'll do some more research on that.
We drove across and checked out some look outs looking back at the dam. Then my dad dropped us and mom and I walked back over- the water level is quite low, the evidence quite visual in a line cut across the banks of lake Mead.
For me, best known from Superman and later from Fools Rush In- the latter in a scene where the two lovers meet in the middle of the dam spanning two states: Nevada and Arizona. That border and others like that- (I'm looking at you Washington and Oregon) are pretty cool. It's the kind of thing movies are made of.