The first park I feel in love with. Actually I was hiking here alot in my early days after moving to Phoenix. This park is beautiful. Sonoran desert, cactus of every shap and size. Beautiful red rocks. A peaceful river with aquatic life. Lots of desert trees. Mesquite, Palo Verde, Ironwood's, Euchalytus, . If you need an escape from the concrete jungle. Papago Park is a good choice for that escape.
If your going to go during the summer months go before 10am and wear a hat, and bring some water. They also have lots of gazeebos scattered throughout the park which can be used for picnics and parties. If you only have one day in Phoenix and you desire to see the desert. I recommend Papago Park. Close enough to every thing. But once your there you'll feel far away from all the stress of the city.