Even if you have only one day, you can experience both the wild and developed parts of Tucson. You can visit the Arizona-Sonora Desert Museum in the morning and combine it with a stop at Mission San Xavier del Bac or Old Tucson Studios. On the way back to town, stop in downtown's Barrio Historico and El Presidio neighborhoods to meander the adobe-lined streets, then have dinner at one of the outstanding Mexican restaurants in downtown or South Tucson.
Another option is spending a half day in Saguaro National Park. Set out in the early morning when it's cooler and the liveliest time for wildlife. If you're based in the Foothills, you can choose Sabino Canyon instead; the saguaros are almost as plentiful and the vistas are equally rewarding. Nature in the morning can be combined with an afternoon in the University area: Visit any of the five campus museums, then stroll University Boulevard and 4th Avenue for ethnic eats and vintage boutiques.
If you have another day for exploring and like to shop, head south to the Mexican border. If you haven't seen Mission San Xavier yet, it's directly en route to Tubac, an artists' colony with historic sights as well as galleries. You can then venture farther south for bargain hunting in Nogales, Mexico (park on the U.S. side and walk across); or head back toward Tucson, stopping at the Titan Missile Museum or at one of the casinos.
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