Washington State Department of TransportationMilepost values at one mile increments on mainline state routes derived from the WSDOT 24K Linear Referencing System for Washington State Routes (LRS). This data is updated annually and represents milepost values on the LRS for the year specified in the LRS_Date field.ArcGIS DynamicMapLayerhttps://hub.arcgis.com/datasets/727f149e4048452dac1b60944d41fef0_2engState of Washington Geospatial Open Data PortalPublicWSDOT - Milepost Values One Mile [Washington (State)]Web servicesWashington (State)Last Modified: 2025-10-07