Arizona... I went in 1998 for the first time to the West coast of USA. I do much regretted I didn't get to see the cactuses typical for Arizona, the Saguaro cactus.
When I went back in 2016 and 2017 I didn't want to miss them. It's amazing how these majestic cactuses are all over the place once you get south enough in Arizona. They can get so old. They're only full grown at 200 years of age.