Administrative Structure of Arizona
Arizona, located in the Southwestern United States, is composed of 15 counties. Admitted to the Union as the 48th state in 1912, Arizona is known for its rich cultural heritage, stunning natural beauty, and dynamic cities. This guide provides a detailed look at Arizona’s county and city structure.
✅Arizona County Map
The map below shows the geographical distribution of Arizona’s 15 counties:
✅Arizona Counties with County Seats, Founded Dates, and Areas
| County | County Seat | Founded | Area (sq mi) | Notes / Major Cities |
|---|---|---|---|---|
| Apache County | St. Johns | 1879 | 11,218 | Large, rural area; Navajo and Apache Nations |
| Cochise County | Bisbee | 1881 | 6,219 | Southeast border county; Douglas, Sierra Vista |
| Coconino County | Flagstaff | 1891 | 18,661 | Includes Flagstaff, Grand Canyon National Park (part) |
| Gila County | Globe | 1881 | 4,796 | Mountainous central region; Payson nearby |
| Graham County | Safford | 1881 | 4,641 | Agricultural valley, southeastern interior |
| Greenlee County | Clifton | 1909 | 1,848 | Smallest by population; mining economy |
| La Paz County | Parker | 1983 | 4,513 | Lower Colorado River corridor; created 1983 |
| Maricopa County | Phoenix | 1871 | 9,224 | Arizona’s largest county by population; Phoenix, Mesa, Scottsdale |
| Mohave County | Kingman | 1864 | 13,461 | Northwest Arizona; Lake Havasu City, Kingman |
| Navajo County | Holbrook | 1895 | 9,960 | Northeast high country; Winslow, Holbrook |
| Pima County | Tucson | 1864 | 9,187 | Second-largest metro area; Tucson |
| Pinal County | Florence | 1875 | 5,374 | Between Phoenix and Tucson; rapidly growing towns |
| Santa Cruz County | Nogales | 1899 | 1,238 | International border county with Mexico |
| Yavapai County | Prescott | 1864 | 8,128 | Central highlands; Prescott, Sedona (partly) |
| Yuma County | Yuma | 1864 | 5,519 | Southwest border; major agricultural center |
Arizona Counties and Their Features
Maricopa County
Area: 9,224 square miles
County Seat: Phoenix
Established: 1871
Most populous county in Arizona and home to the state capital, Phoenix.
Pima County
Area: 9,189 square miles
County Seat: Tucson
Established: 1864
Home to Tucson and the Saguaro National Park.
Pinal County
Area: 5,374 square miles
County Seat: Florence
Established: 1875
One of the fastest-growing counties in the United States.
Yavapai County
Area: 8,128 square miles
County Seat: Prescott
Established: 1864
Known for its picturesque landscapes and historic mining towns.
Yuma County
Area: 5,519 square miles
County Seat: Yuma
Established: 1864
Borders both California and Mexico, with extensive agricultural areas.
Coconino County
Area: 18,661 square miles
County Seat: Flagstaff
Established: 1891
Home to the Grand Canyon and the largest county by area in Arizona.
Major Cities in Arizona
Phoenix
County: Maricopa
Incorporated: 1881
State capital and most populous city in Arizona. Known as the “Valley of the Sun.”
Tucson
County: Pima
Incorporated: 1877
Home to the University of Arizona and surrounded by five mountain ranges.
Mesa
County: Maricopa
Incorporated: 1883
Third-largest city in Arizona and a major suburb of Phoenix.
Chandler
County: Maricopa
Incorporated: 1920
Known for its technology industry and sometimes called “Silicon Desert.”
Scottsdale
County: Maricopa
Incorporated: 1951
Known for its luxury resorts, golf courses, and vibrant art scene.
Glendale
County: Maricopa
Incorporated: 1910
Home to State Farm Stadium and the NHL’s Arizona Coyotes.
Geographical and Cultural Diversity
Arizona’s counties encompass a wide range of geographical features, from the Sonoran Desert in the south to the Colorado Plateau in the north. The state is home to 22 federally recognized Native American tribes, and each county has its own unique cultural and historical significance.
The variation in population density across counties reflects both the state’s urban centers and its vast rural areas, with Maricopa County being one of the fastest-growing regions in the United States.