The Historic American Engineering Record documents important engineering and industrial sites in the United States. It was formed by the National Park Service, the Library of Congress and the American Society of Civil Engineers. The results of their surveys are archived along with the Historic American Building Survey at the Library of Congress. There is a searchable catalog online. So much history is lost when knowledge dies out along with individuals, and it is almost impossible to know what we important information we are losing each day. Reverse-engineering historical places and equipment before they decay and preserving what knowledge we do have available is important.