Desert Mountains and Saguaro Cacti
Here you will find free camping on BLM land in the Sonora Desert National Monument (BLM page link). It's easy access from AZ 85. We took BLM road 8000, north of Gila Bend, into washy, sand roads and found easy dispersed camping within 20 minutes of the highway. There was no water here, and less cell service. Not to mention it seems to be a less popular area, so if you're looking to get away under the desert mountains and Saguaro Cactus's this is your place! This is just south of Phoenix for you city folk.