Winter or summer? The desert is gorgeous in fall, winter, and spring, but not for the inexperienced in the summer. In the late fall or winter, I love Death Valley. Camp at Sunset inside the park if you can handle dry camping. Joshua Tree is gorgeous too with rocks in fantastic forms. We stayed at Belle campground, no reservations, but big sites were available. Anywhere along the east side of the Sierras along US-395 is awfully nice with historic sites. The west side of the Sierras has all the National Parks and lots of fascinating mining history. Southwest Arizona has the Lake Havasu area, though we prefer the area outside of the town itself. Yuma is full or snowbirds and services for them. We like the area around Tucson better than around Phoenix, and the Saguaro National Monument was outstanding with much more than saguaro.