King CountyFor more information about this layer please see the GIS Data Catalog . Expanded layer built on CITY_3CO_AREA., CITY_3CO_UNINC_AREA is a compilation of city jurisdictional information from three counties: King, Pierce and Snohomish, plus the unincorporated areas in each of the three counties. Uses the best available information from each of the 3 counties to produce the composite product for the jurisdictional areas and assumes the areas outside of the jurisdictions to be unincorporated. Updated whenever changes are made to any one of the source data sets. For King County this will be whenever CITY_AREA (parent is CITY_ANNEX) is updated to Spatial Data Warehouse. Pierce and Snohomish updates are shared with King County on quarterly to semi-annual basis. Updates are made so that the King County portion of this composite is synchronous with the information in the master King County jurisdiction layer.ArcGIS FeatureLayerhttps://hub.arcgis.com/datasets/fa25985422f3453bae05167a614cccff_0engKing County GIS Open DataPublicIncorporated areas of King; Snohomish; and Pierce Counties; plus Unincorporated Areas [Washington (State)--King County]Web servicesWashington (State)--King CountyWashington (State)Last Modified: 2026-01-15