Wizard Rock, a landmark known for its black and white streaks of quartz, was reported missing about two weeks ago.
Parks officials are happy to have it back.
"We are thrilled the Wizard Rock was returned, and are grateful that whoever took it was conscientious enough to give it back to the public," Sarah Clawson, a ranger for Prescott National Forest's Bradshaw Ranger District, said in a statement. "National forests provide so many benefits to the American people, and when something like this happens, it highlights the intrinsic value of natural beauty in all its forms."
Park staff believe it would have taken heavy equipment to move the large rock, The Arizona Republic reported.
Officials are now considering moving the rock to another location where it could still be seen by visitors.
The Associated Press contributed to this report.
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