Joshua Tree, Zion, Bryce Canyon and Arches. My four favourite US National Parks (the only national parks I've been to so far, so it’s not as big of an honour as it sounds).
1) Joshua Tree National Park
Huge, bedrock-esque boulders mixed in with flat plains filled with alien-looking trees (aka the Joshua Tree) and cacti make up this arid and prickly desert.
2) Zion National Park
Giant pink and white buttes with sharp cliffs, pinyon pines and junipers trees fill this area as well as steep lookouts and hair-raising hikes with scenic vistas.
3) Bryce Canyon National Park
Thousands of hoodoos competing to be the tallest and weirdest looking, red sand hikes and a pinyon pine forest (which I sadly have no photos of).
4) Arches National Park
Arches (obviously) of all shapes, sizes and girths, layered pastel landscapes and plant life that would make a classic white girl drool.