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It is the largest county in the United States to have a capital city. It is by far Arizona's most populous county, encompassing well over half of the state's residents. From west to east, it stretches 132 miles (212 km), and 103 miles (166 km) from north to south. Maricopa County is one of the largest counties in the United States by area, with a land area greater than that of four other US states.
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The largest are the Salt River Pima-Maricopa Indian Community (east of Scottsdale) and the Gila River Indian Community (south of Chandler).Īccording to the United States Census Bureau, the county has a total area of 9,224 sq mi (23,890 km 2), of which 24 sq mi (62 km 2) (0.3%) is covered by water.
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Five Native American Reservations are located in the county. Maricopa County was named after the Maricopa Native Americans. Previously, it was the Phoenix–Mesa–Glendale metropolitan area, and in 2000, that was changed to Phoenix–Mesa–Scottsdale. The Office of Management and Budget renamed the metropolitan area in September 2018. Maricopa County is the central county of the Phoenix–Mesa–Chandler Metropolitan Statistical Area. The county seat is Phoenix, the state capital and fifth-most populous city in the United States.
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As of the 2020 census the population was 4,420,568, or about 62% of the state's total, making it the fourth-most populous county in the United States, the most populous county in Arizona, and making Arizona one of the nation's most centralized states. Maricopa County is in the south-central part of the U.S.
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