Merrimack County, New Hampshire

Merrimack County is a county in the U.S. state of New Hampshire. As of the 2020 census, the population was 153,808, making it the third-most populous county in New Hampshire. Its county seat is Concord, the capital of New Hampshire. The county was founded in 1823 from parts of Hillsborough and Rockingham counties, and is named for the Merrimack River.

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Category:1820s establishments in New Hampshire
Category:1823 establishments in the United States
Category:New Hampshire counties