Once a vast, open space dotted with horse ranches, Northwest Tucson is now a rapidly growing residential area encompassing the townships of Oro Valley and Marana. Families and retirees are moving here in droves, and the traffic congestion proves the point, but you'll also find first-rate golf resorts and restaurants here, as well as the oases of Tohono Chul Park and Catalina State Park, which calm the senses.
The Westside is far less developed, and beautiful vistas of saguaro-studded hills are around every bend. Saguaro National Park West, the Desert Museum, Old Tucson Studios, and the San Xavier mission are all in this section of town. If you're interested in the flora and fauna of the Sonoran Desert—as well as some of its appearances in the cinema—heed the same advice given the pioneers: go west.