The Public Land Survey System (PLSS) is the way land in the United States is subdivided, it forms the foundation of Cook County's cadastral system for identifying and locating land records. Tax parcels are identified using township and section notation, in a modified format. The PLSS serves as a way for users to navigate the parcel geodatabase. This PLSS feature data set is intended to correspond to tax pages on the Cook County Tax Maps. They should not be used for measurement or surveyor purposes. In addition, the parcel attributes PINA (area/township) and PINSA (subarea/section) do not necessarily correspond to the PLSS township and section polygon in which a given parcel resides. The PLSS data is modeled as a single composite network coverage that encompasses townships (area), sections (subarea), quarter sections, and half quarter section. Tax map pages, which typically correspond to half quarter sections (in an east-west split), are modeled as a region subclass in the LANDFABRIC layer. If an indigenous people's reserve was present on the tax map, it was digitized to create subpolygons of the half-quarter section, and those polygons were attributed with the name of the reserve. Within this PLSS data set, a half-quarter section is the smallest polygon unit, except in cases where an Indigenous People's Reserve line is present. The cadastral data for Cook County have previously not been digital nor automated. This project is the initial automation for this information. This database was designed to represent a continuous, non-overlapping spatial database accounting for all land area in Cook County.The PLSS is updated as needed.

Forest Preserve District of Cook County boundaries. To view or use these shapefiles, compression software and special GIS software, such as ESRI ArcGIS, is required.

Geospatial data about Cook County, Illinois ZIP Code Boundary. Export to CAD, GIS, PDF, CSV and access via API.

Forest Preserve District of Cook County boundaries. To view or use these shapefiles, compression software and special GIS software, such as ESRI ArcGIS, is required.

Cook County GIS Department map of municipal boundaries in Cook Cook County, Illinois in PDF format. Includes major streets, waterbodies, rail, Cook County Forest Preserve, and municipal boundaries.

Cook County Municipalities layer displays the boundaries of all municipalities within Cook County, IL.

© Cook County GIS Department This layer is a component of Boundary data layers for the Green Infrastructure Atlas.

© Calumet Stormwater Collaborative & South Suburban Mayors and Managers Association

Cook County GIS Department map of municipal boundaries in Cook Cook County, Illinois in PDF format. Includes major streets, waterbodies, rail, Cook County Forest Preserve, and municipal boundaries.

KML file of the boundaries of Cook County Forest Preserve facilities. To view or use these files, special GIS software such as Google Earth is required

Dissolved parcel-level data displaying the boundary of all property currently owned or leased by the Forest Preserve District of Cook County.Source data is maintained by the Forest Preserve District's Planning and Development Department (GIS Section) and uploaded to this layer daily.

This layer is a component of GIV Hydrology Layers.

This layer is a component of GIV Planning Data Layers.

© Calumet Stormwater Collaborative & South Suburban Mayors and Managers Association

Cook County GIS Department map of Cook County Commissioner District 14 in PDF format. Includes major streets, waterbodies, rail, and Cook County Commissioner District boundaries.

The purpose of this dataset is to indicate the boundary of each park in Cook County, Illinois.

The TIGER/Line shapefiles and related database files (.dbf) are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) Database (MTDB). The MTDB represents a seamless national file with no overlaps or gaps between parts, however, each TIGER/Line shapefile is designed to stand alone as an independent data set, or they can be combined to cover the entire nation. Face refers to the areal (polygon) topological primitives that make up MTDB. A face is bounded by one or more edges; its boundary includes only the edges that separate it from other faces, not any interior edges contained within the area of the face. The Topological Faces Shapefile contains the attributes of each topological primitive face. Each face has a unique topological face identifier (TFID) value. Each face in the shapefile includes the key geographic area codes for all geographic areas for which the Census Bureau tabulates data for both the 2020 Census and the annual estimates and surveys. The geometries of each of these geographic areas can then be built by dissolving the face geometries on the appropriate key geographic area codes in the Topological Faces Shapefile.

This layer contains polygons representing land that is under the jurisdiction of the Illinois Nature Preserves Commission (INPC), being designated either as a Nature Preserve, Nature Preserve buffer, or Land & Water Reserve and lying within the boundaries of the Forest Preserve District of Cook County. Actual nature preserve boundaries may vary slightly from GIS polygons shown and should be verified with legal descriptions provided by INPC and Cook County Recorder of Deeds. For more information on Illinois Nature Preserves and the INPC, please visit: Illinois Nature Preserves Commission WebsiteSource data is maintained by the Forest Preserve District's Planning and Development Department (GIS Section) and uploaded to this layer daily.

Cemetaries located in Cook County. To view or use these shapefiles, compression software and special GIS software, such as ESRI ArcGIS, is required.

Neighborhood polygons used by the Cook County Assessor's Office for valuation and reporting. These neighborhoods are specific to the Assessor. They are intended to represent homogenous housing submarkets, NOT Chicago community areas or municipalities.

These neighborhoods were reconstructed from individual parcels using spatial buffering and simplification. The full transformation script can be found on the Assessor's GitHub.

Read about the Assessor's 2023 Open Data Refresh.

Cook County GIS Department map of Cook County Commissioner District 10 in PDF format. Includes major streets, waterbodies, rail, and Cook County Commissioner District boundaries.

The purpose of this dataset is to indicate the boundary of each Commissioner district in Cook County, Illinois. These boundaries are based off of Census 2020 geographies, were adopted September 23, 2021, and will go into effect on December 5, 2022.

KML file of Cook County facilities. To view or use these files, special GIS software such as Google Earth is required.