Almost all of the Circle Ks in the area sell them. Ask for a Tonto pass. The pass is good for any of the recreation areas in the Tonto National Forest. Only $8.
They have a machine at Saguaro Lake. Not sure if they installed a machine at Granite Reef. I buy an annual pass from the Fish and Game in Mesa.
Almost any retail establishment going up Power Road has them. There are two Walgreens on the way in, both have passes, and almost all the gas stations on the way in carry them too.
If it is like Prescott's parks there should be a paying station by entrance.
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