The Coronado National Forest covers approximately 1.78 million acres across southeastern Arizona and southwestern New Mexico, but it isn't one contiguous forest — the U.S. Forest Service describes it as a dozen widely scattered mountain ranges, each rising like an island out of the surrounding desert. This is the Sky Islands region, and the Pinaleño Mountains, home to Mount Graham, are among its most dramatic examples, with elevations across the forest ranging from about 3,000 feet to the 10,720-foot summit of Mount Graham itself.
What's Inside the Forest Near the Gila Valley
For Gila Valley visitors, the Coronado National Forest is best known through the Pinaleño Mountains unit, reached via Swift Trail Parkway (AZ-366). This portion of the forest includes Riggs Flat Lake, Hospital Flat Campground, Frye Mesa Reservoir, and the Santa Teresa Wilderness, offering everything from alpine fishing and camping to backcountry hiking. Because the forest spans such a wide elevation range, it supports desert scrub, oak woodland, ponderosa pine, and spruce-fir forest all within the same general area, along with wildlife found nowhere else in this part of Arizona, including the endangered Mount Graham red squirrel.
Visiting Tips
Access varies by season: high-elevation roads and campgrounds in the Pinaleños typically close from mid-November through mid-April due to snow, while lower-elevation trails and recreation sites are often usable year-round. Fees, permits, and road conditions can change, so check current information with the Coronado National Forest office before a trip, especially for camping or areas near the summit of Mount Graham, where habitat protections restrict access above roughly 9,800 feet. Parts of the high country near the summit still show burn scars from the 2017 Frye Fire, though much of the forest, including areas around Riggs Flat Lake, remains green and heavily forested. Because the forest is so spread out, most Gila Valley visitors focus on the Pinaleño unit and pair a visit with nearby Roper Lake State Park or Dankworth Ponds for a mix of mountain and valley recreation.