
				Pat Quinn, Governor

IHPA Links

IHPA Home

Presidential Museum

Historic Sites

Preservation Services

Library Catalog

HAARGIS Help

Getting Started
Map Tools
About the Layers
Searching
Reports
Feedback

About the Layers

HAARGIS consists of spatial data sets having the same coordinates in space that are layered on top of each other to create the map image. Click on the Legend in the Links area for identification of map symbols. We have set specifications for each layer based on common usage--for example, at all extents, you can see the properties layer and the county boundaries; you must zoom in to the county level before you can see city boundaries; you must zoom into the city boundaries to see NRHP districts, and so forth. Even though these layers and the extent at which they are visible are set by default, users can turn layers on and off by clicking on the Layers On/Off tab on the Legend.

Turning Layers On/Off

To improve your map view, turn on only those layers that are important to you. With the Legend visible, click on the Layers On/Off tab. The layers that are presently visible in the map have a check mark next to them. Uncheck the box to turn off a layer, or check the box to turn a layer on. Click the "Refresh Map" button to display the changes.

Depending on the extent of the map view some layers will not be available to turn on. The extents at which each layer is available is given within the following section.

Description of the Layers

Each of these layers available in HAARGIS is described in detail below. We will be adding to some of the layers continuously, so please check back here often:

Standing Structure Surveyed Properties: These points have been plotted by Preservation Services staff for the following properties:

Those properties on the National Register of Historic Places (NRHP). Each district has a point located in the center of the district as well as district boundaries identified by polygons in the National Register Districts layer.
Those properties that have been determined eligible for the NRHP. This includes bridges on the Historic Bridge Survey and other properties designated eligible for the NRHP by the Keeper.
Those properties that were included in the Illinois Historic Structures Survey.
Those properties that were included in the Illinois Historic Landmarks Survey.
Local landmarks identified by the following Certified Local Governments (an asterisk indicates that there are districts entered in the CLG Districts layer):
- Commission on Chicago Landmarks *
- Crystal Lake Historic Preservation Commission
- Danville Historic Preservation Commission
- Elgin Heritage Commission
- Galesburg Landmark Commission
- Geneva Historic Preservation Commission *
- Highland Park Historic Preservation Commission
- Jacksonville Historic Preservation Commission
- Joliet Historic Preservation Commission
- Lake Forest Historic Preservation Commission
- McHenry County Historic Preservation Commission *
- Moline Historic Preservation Commission
- Normal Historic Preservation Commission *
- Oak Park Historic Preservation Commission
- Riverside Preservation Commission
- Rockford Historic Preservation Commission *
- Rock Island Preservation Commission *

Note: NRHP properties were verified by maps available in the office; non-NRHP properties were geoaddressed (plotted automatically by their address) and have not been individually verified. We are presently adding properties and districts that have been determined local landmarks by CLGs, and will add properties from the Illinois Rural Survey, and a number of community surveys before we are done. This layer is turned on at all extents.

City boundaries: This layer was obtained from the Illinois Natural Resources Geospatial Data Clearinghouse. It is turned on by default and is visible at approximately a county-view extent.

County boundaries: This layer was obtained from the Illinois Natural Resources Geospatial Data Clearinghouse. It is turned on by default and is visible at all extents.

National Register districts: These polygons were plotted by staff at the Illinois State Museum and by Preservation Services staff from maps available in this office. These are approximate boundaries based primarily on city streets (specific verbal boundaries can be found in the NRHP application for the district). These are turned on by default and are visible at approximately a city-view extent.

Certified Local Government (CLG) Districts: These polygons were plotted by Preservation Services staff from maps available in this office. Presently only the CLG district in McHenry County is available in this layer. This layer is turned off by default, but can be turned on at the city-view extent.

Local Governments: These polygons were created by Survey staff based on the status of a city or county as a (CLG). This layer is turned off by default, but can be turned on at the county-view extent.

Interstate: These lines were created from the Topologically Integrated Geographic Encoding and Referencing (TIGER®) database of the United States Census Bureau in 2000. They are turned on by default at approximately the half-state view extent.

US Highways: These lines were created from the Topologically Integrated Geographic Encoding and Referencing (TIGER®) database of the United States Census Bureau in 2000. They are turned on by default at approximately the county-view extent.

State Roads: These lines were created from the Topologically Integrated Geographic Encoding and Referencing (TIGER®) database of the United States Census Bureau in 2000. They are turned on by default at approximately the county-view extent.

Other Roads: These lines were created from the Topologically Integrated Geographic Encoding and Referencing (TIGER®) database of the United States Census Bureau in 2000. They are turned on by default at approximately the city-view extent.

High Probability Archaeology: This layer was created by the Illinois State Museum. It is turned off by default but can be turned on at any extent.

Public Land Survey System (PLSS): This layer represents the Public Land Survey System (section, township, and range boundaries). It was received from the Illinois State Geological Survey. It is turned off by default, but can be turned on at approximately the city-view extent.

Streams: This layer was obtained from the Illinois Natural Resources Geospatial Data Clearinghouse. It is turned on by default at the city-view extent.

Railroads: This layer was obtained from the Illinois Natural Resources Geospatial Data Clearinghouse. It is turned on at the city-view extent.

Chicago Community Areas (CA): This layer of the boundaries of Chicago Community Areas was received from the Northeastern Illinois Planning Commission. It is turned off by default and can be turned on at any extent.

Federal Lands: This layer was obtained from the Illinois Natural Resources Geospatial Data Clearinghouse. It is turned off by default and can be turned on at any extent.

Floodplain: This layer was obtained from the Federal Emergency Management Agency. It is turned off by default, but it is available at the city-view extent.

House district boundaries: This layer was received from the Illinois Department of Natural Resources. It represents the 2001 boundaries of the Illinois House of Representatives. It is turned off by default, but it can be turned on at all extents.

Senate district boundaries:This layer was received from the Illinois Department of Natural Resources. It represents the 2001 boundaries of the Illinois Senate. It is turned off by default, but it can be turned on at all extents.

Orthophotos: Orthophotos are aerial photographs that have had geographic coordinates added to them so they can be used with other feature layers and electronic mapping software. The orthophotos were produced by the United States Geographic Survey under the National Area Photography Program. These images can be turned on at approximately a one mile-extent. These images and the USGS Topographical Map images are mutually exclusive.

United States Geographical Survey (USGS) Topographical Maps: These images of commonly-used USGS maps show the shape and elevation of the terrain. They include drainage (lakes and rivers), forest cover, populated areas, transportation routes, and mark prominent natural and cultural features. These images can be turned on at approximately a one mile-extent. These images and the Orthophoto images are mutually exclusive.