King CountyFor more information about this layer please see the GIS Data Catalog . A five-tier system that categorizes all roads in the county road system. Tier 1 roadways are primarily principal arterials and lifeline routes that serve the greatest number of users (highest priority), while Tier 5 roadways are local roads that do not provide the sole access for people to get to their homes (lowest priority).ArcGIS FeatureLayerhttps://hub.arcgis.com/datasets/c38f64cb96d1411793772c009af77499_0engKing County GIS Open DataPublicRoads Service Levels [Washington (State)--King County]Web servicesWashington (State)--King CountyWashington (State)Last Modified: 2025-08-20