Deem Hills, located west of I-17 near Happy Valley Road, makes up almost 1,000 acres of Arizona Upland vegetation. Its characteristic black rock is a dark lava called basalt, and other volcanic rock such as granite formulate the landscape. The area showcases a variety of native desert vegetation such as saguaros, barrel cacti, buckhorn cholla, brittlebush, ocotillo, creosote, globe mallow and Palo Verde trees.
A variety of trails are located within Deem Hills. The Deem Hills Circumference trail at 5.7 miles traverses the entire recreation area and commands excellent views of the Phoenix area, and connects the trailhead parking lots at 39th Ave. and Pinnacle Vista and Deem Hills Community Park to the west. The Ridgeline trail runs 1.5 miles and is the highest trail in elevation in the system. It can be strenuous so exercise caution. Several shorter trails provide a wide range of both distance and difficulty from this location.