Few sights evoke the American West more than the saguaro cactus, found only in the Sonoran Desert. Saguaro National Park, close to the urban center of Tucson, Arizona, protects these majestic cacti. At the park, you can hike through fantastic desert scenery year-round. Sunset photo byDavid Olsen. Posted on Tumblr by the US Department of the Interior, 12/16/16.