Formed November 11, 1875 (24th county)
Columbia County (3,952), Dayton (2,445)
The 1887 Late Victorian structure is the original building with 1938 and 1993 remodelings. The facility is located on Main Street between 2nd and 3rd streets. Main Street is United States Highway 12 in the town. W. H. Burrows provided the masonry building designs. It features a tower and Lady Justice. A canon sits on the grounds. Columbia County was formed from Walla Walla County on November 11, 1875 as the 24th county with Dayton as the only county seat. The county is named for the Columbia River. The county seat was named for settler Jesse N. Day.
Columbia County government consists of a sheriff, an attorney, a clerk, a treasurer, an auditor, and an assessor (executive). It has 3 Commissioners (legislative.) One Superior Court Judge serves Columbia, Asotin, and Garfield counties and One District Court Judge serves Columbia County (judicial.) The county is on the southeast border with Oregon. The Snake River forms its northern border. Spokane, Washington is north and Seattle, Washington is northwest of the county. The county center is 5.2 miles East of Dayton. The county is surrounded clockwise by Whitman and Garfield and Oregon and Walla Walla and Franklin counties.
The area of the county is 869 square miles. It ranks 31 out of 39 in area in the state. It is 38 out of 39 in population in the state. It has a density of 4.5 persons per square mile making it 37 out of 39 in the state. Columbia County has 64.9% of its population in its incorporated areas. It is 31 out of 39 in the state. United States Highway 12 enters the county from the east, Garfield County, and exits to the southwest, Walla Walla County. The county resembles a stealth airplane flying northeast. Dayton is located west of center in the county. Dayton is the county seat and the largest city. It is 61.9% of the county population.
Dayton
Starbuck
