In 1969, the Historic American Engineering Record (HAER) section of the Heritage Documentation Program of the National Park Service was started to document historic sites and structures related to engineering and industry. It conducts a nationwide documentation program in partnership with state and local governments.
The documentation produced by HAER provides a permanent record of the nation’s most important historic sites and large-scale objects and provides a baseline documentation for rehabilitation and restoration that makes available well-researched materials for historic interpretation and illustration. This documentation is produced in three parts: large-format photography, written history and measured drawings. These documents were produced by the HAER section in coordination with ARDOT.