Thompson Peak is a 3,984-foot mountain in the McDowell Mountains about 20 miles northeast of Phoenix, Arizona, rising near the desert edge by Fountain Hills as one of the range’s prominent summits. Beyond its visual prominence in the landscape, the summit serves a practical purpose through radio towers installed for amateur use and for Maricopa County government. A service road from Fountain Hills reaches these facilities, linking the peak’s commanding position to its role in regional communications.