SEATTLE, Washington - I have a laminated map where I've marked with a black marker everywhere I've been. Given my prodigious memory, I think it's close.
Nevada has a bit of a unique look on the map - it looks like it won't let intruders into its interior. I have six entry/exit points, from lonely Jackpot in the north (where the desolate two-lane road generously grows a turning lane to allow for easy access to Jackpot's modest casinos) to several entries near Las Vegas. It looks like I have entered and been steered right back out, like there is some great secret in Ely or Winnemucca that I'm simply not allowed to see.
Compare this with nearby, promiscuous California, which I have crisscrossed with impunity.