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Illinois Historical Aerial Photography Metadata

Metadata is often defined as "data about data." This project has been supported by many grants and contracts, all of which have required the creation of metadata files as a project deliverable. However, satisfying each contract has required conforming to a variety of documentation standards, and thus has resulted in multiple collections of metadata. This page provides you with access to all of the metadata collections regarding digital Illinois Historical Aerial Photography (ILHAP) files.

Federal Geographic Data Committee (FGDC) Metadata
Although the photographs in this collection have not been georeferenced, collection-level FGDC Metadata is provided due to the geographic nature of this digital collection and because the files are provided via a National Spatial Data Infrastructure (NSDI) Clearinghouse. Four individual FGDC metadata files, representing different aspects of the project, are available as a bundle and also separately. The FGDC Metadata files are updated every time the ILHAP ArcIMS Interactive Map Service is updated.

The bundled file,, contains the following individual files:
  • ilhap_gen, overall metadata for the county aerial photograph collections.
  • ilhap_nav, generic metadata for the county index data layers.
  • l_index, metadata for the schematic (line) indexes.
  • p_index, metadata for the photo mosaic indexes.

Dublin Core Metadata (Dublin Core)
"Dublin Core" refers to the Dublin Core Metadata Initiative (DCMI), which is the body responsible for the ongoing maintenance of the Dublin Core metadata standard. DCMI is currently hosted by the Online Computer Library Center, Inc. (OCLC), a not-for-profit international library consortium. ILHAP Dublin Core Metadata records are listed for each county. The records are added as each new county is made available on-line.

51 records are available at the Illinois State Library - Illinois Digital Archives (IDA):
MAchine-Readable Cataloging (MARC)
MARC defines a data cataloging format that emerged from a Library of Congress-led initiative. It provides the mechanism by which computers exchange, use, and interpret bibliographic information, and its data elements make up the foundation of most library catalogs used today. This metadata format is primarily used by libraries and librarians. ILHAP MARC catalog records are provided by county. The catalog records are added as each new county is made available on-line.

57 records are available through WorldCat:
  • County Collections, non alphabetical list created from an automatic search for "digital archive of Illinois historical aerial photographs."
  • Specific County Collection, enter "digital archive of Illinois historical aerial photographs" and the "county name."