Chesapeake & Ohio Canal Historic Resource Study (by Harlan Unrau)
On January 8, 1971, President Richard M. Nixon signed into law the bill creating the Chesapeake & Ohio Canal National Historical Park. In the mid-1970s, National Park Service historian Harlan D. Unrau produced a major, handwritten, multi-volume study of the history, engineering, operation, maintenance, and other aspects of the Chesapeake & Ohio canal. A rough, unedited typed version was produced in the early 1980s for general use by park staff.