Columbia County, Washington

Columbia County is a county in the U.S. state of Washington. The county seat is Dayton. 3,952 people lived there at the 2020 census which makes it the third-least populous county in Washington. The county was created out of Walla Walla County on November 11, 1875 and is named after the Columbia River.

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Category:1875 establishments in Washington (state)
Category:Washington (state) counties