Map of Arizona Regions

Arizona is one of the few states where “which part of Arizona?” changes almost everything about the answer — the elevation, the temperature, the vegetation, even whether it snows. The state spans nearly 12,000 feet of vertical relief, from 70 feet above sea level on the Colorado River near Yuma to 12,633 feet at the summit of Humphreys Peak outside Flagstaff. A map of Arizona regions is really a map of that vertical range, because in Arizona geography follows elevation far more closely than it follows latitude.

Geologists split the state into three physiographic provinces. The Colorado Plateau covers the northeastern two-fifths: high, flat-lying sedimentary rock between 5,000 and 8,000 feet, sliced open by the Grand Canyon and a hundred smaller canyons. The Basin and Range covers the southwest: broad desert valleys separated by isolated, north–south mountain ranges rising abruptly from the flats. Between them runs the Transition Zone, a rugged diagonal belt along the Mogollon Rim where the plateau breaks off in an escarpment that drops as much as 2,000 feet in one step. Everyday Arizona usage splits the same land into four or five named regions, which is how the table below is organised.

Arizona Regions at a Glance

Northern Arizona

Northern Arizona is the high country: Coconino, Navajo and Apache counties, plus the isolated Arizona Strip in northern Mohave County cut off from the rest of the state by the Grand Canyon. Almost all of it sits above 4,500 feet, and the ponderosa pine belt around Flagstaff is the largest contiguous ponderosa forest in the world. Flagstaff receives around 100 inches of snow in an average winter — a fact that surprises anyone whose mental image of Arizona is saguaro cactus.

This region holds a disproportionate share of the state’s famous landscapes: Grand Canyon National Park, Monument Valley, Petrified Forest National Park, Antelope Canyon, Horseshoe Bend and Canyon de Chelly. Much of the land is tribal: the Navajo Nation covers the northeast corner, with the Hopi Reservation entirely enclosed within it. Note that the Navajo Nation observes daylight saving time while the rest of Arizona does not, so clocks in that corner run an hour ahead of Phoenix from March to November.

Central Highlands

The Central Highlands run diagonally across the middle of the state, following the Mogollon Rim through Yavapai and Gila counties. This is the in-between country — too high for saguaros, too low for the aspen and spruce of the San Francisco Peaks — and it is where the red rock of Sedona, the Victorian streets of Prescott, the Verde Valley vineyards and the cliff-hanging former copper town of Jerome all sit. Summer temperatures typically run 15 to 20°F cooler than Phoenix, which is why the region fills with Valley residents from June to September.

Central Arizona and the Valley of the Sun

The Sonoran Desert basin holding Phoenix and its suburbs is where roughly three in five Arizonans live, in Maricopa and northern Pinal counties. Elevation here is only 1,000 to 2,000 feet, which is what produces the summer heat: 110°F afternoons are routine in July. The compensation is a mild winter and a desert that is genuinely green by desert standards, with saguaro, palo verde and ocotillo growing thickly on the surrounding bajadas.

Southern Arizona

South of the Gila River, the Basin and Range takes on its most dramatic form: the Sky Islands, isolated mountain ranges rising 5,000 feet or more out of the desert, each carrying its own forest ecosystem. Pima, Santa Cruz, Cochise, Graham and Greenlee counties make up the region, anchored by Tucson. Mount Lemmon above Tucson climbs from saguaro to conifer in about 25 road miles — ecologically the equivalent of driving from Mexico to Canada. All four Arizona ports of entry into Mexico are in this region.

Western Arizona

Western Arizona is the Colorado River corridor, running the full length of the state’s western boundary through Mohave, La Paz and Yuma counties. It is the hottest and driest part of Arizona — Yuma averages more sunshine than anywhere else recorded on Earth and receives around three inches of rain a year — but the river makes it a water-recreation destination, with Lake Havasu, Lake Mohave and Lake Mead drawing boaters year-round. Yuma’s irrigated fields also produce most of the leafy greens eaten in the United States between November and March.

Choosing a Region to Visit

The practical rule is seasonal: visit northern Arizona and the highlands between May and October, and southern and western Arizona between October and April. Trying it the other way round means either snow-closed roads on the Rim or 115°F afternoons in Yuma. Spring and autumn are the two windows when every region is comfortable at once, and they are correspondingly busy.

To go deeper, browse the Arizona county map for administrative boundaries, the map of Arizona cities and towns for population centres, the Arizona road map for the highways linking the regions, or the parks and natural wonders map for what to see in each.