Maricopa County, Arizona

Maricopa County is located in the central part of the U.S. state of Arizona. As of July 2006 its population was 3,768,123, which ranks fourth among the nation's counties and is greater than the population of 23 states. The county seat is Phoenix, which is Arizona's largest city and capital. The center of population of Arizona is located in Maricopa County, in the town of Gilbert [1]. It is Arizona's most populous county.
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