Wahkiakum County, Washington

Wahkiakum County, Washington
Wahkiakum County Courthouse in Cathlamet
Location within the U.S. state of Washington
Coordinates: 46°17′N 123°26′W / 46.29°N 123.43°W / 46.29; -123.43
Country United States
State Washington
FoundedApril 24, 1854
Named afterChief Wahkiakum
SeatCathlamet
Largest townPuget Island
Area
 • Total
287 sq mi (740 km2)
 • Land263 sq mi (680 km2)
 • Water24 sq mi (62 km2)  8.3%
Population
 (2020)
 • Total
4,422
 • Estimate 
(2024)
4,800
 • Density16.8/sq mi (6.49/km2)
Time zoneUTC−8 (Pacific)
 • Summer (DST)UTC−7 (PDT)
Congressional district3rd
Websitewww.co.wahkiakum.wa.us

Wahkiakum County (/wəˈk.əkʌm/ wə-KY-ə-kum) is a county located in the U.S. state of Washington. As of the 2020 census, the population was 4,422, making it the third-least populous county in Washington. The county seat and only incorporated town is Cathlamet. The county was formed out of Cowlitz County in April 1854 and is named for Chief Wahkiakum ("Tall Timber") of the Chinook, who is buried in the Pioneer Cemetery in Cathlamet.

The county operates the Wahkiakum County Ferry, which connects Cathlamet to Westport, Oregon, across the Columbia River.