With World War I came a new chapter. The U.S. Army purchased the entire tract, including Fort Duffield, as part of the establishment of Camp Henry Knox, later Fort Knox. The hill became part of a vast military reservation focused on training, armor, and national defense.

“With the advent of World War I, the entire property was purchased by the U.S. Army for the establishment of Camp Henry Knox…”

For more than half a century, the fort saw little direct use. The Army’s needs lay elsewhere on the reservation, and Fort Hill remained largely wooded and undisturbed. This long period of neglect ironically preserved the Civil War earthworks better than many more famous sites.

In the late twentieth century, regional efforts like Radcliff’s “Bridges to the Past” project and growing interest in heritage tourism began to draw attention to historic sites near Fort Knox. Fort Duffield’s potential as a preserved earthwork and cemetery fit naturally into this emerging narrative.