An hour east of Phoenix, or just 90 minutes north of Tucson, is the Boyce Thompson Arboretum, Arizona's oldest and largest botanical garden. No matter which city you might be visiting, this desert oasis is one of the best day-trips you can take. (My wife and I made a day of it from Tucson, first visiting the pre-Columbian ruins at Casa Grande Nat'l Monument, then continuing through the Old West town of Florence before ending up here at the Arboretum.)
In addition to native Sonoran Desert vegetation, the gardens feature specimens from deserts all over the world, making this a truly 'international oasis.' It's jointly run by the state as a state park and also by the University of Arizona. Founded in the 1920's, this is one of the best places to be outside in Arizona...
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