About Mercer County

Mercer County is 226 square miles and sixteenth in size of the twenty-one New Jersey counties. About 1.7 million people live within 25 miles of Mercer County and 1-10th of the population of the United States lives within a seventy five mile radius of the County.

Mercer County was formed in 1838 from parts of Burlington, Middlesex, Somerset, and Hunterdon Counties. Mercer County consists of thirteen municipalities, including Trenton, which serves as both the State Capital and County Seat. The County Executive and Board of Chosen Freeholders are the locally elected officials in Mercer County's Government.

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