Columbia subject headings:
Coast defenses--United States--History.
Fortification--United States--History.
Fortification--Virginia--Hampton Roads (Region)--History.
United States. Army. Corps of Engineers--History.
Harvard subject headings:
Coast defenses--United States--History.
Fortification--United States--History.
Fortification--Virginia--Hampton Roads--History.
United States. Army. Corps of Engineers--History.
Princeton subject headings:
Coast defenses--United States--History.
Fortification--United States--History.
Fortification--Virginia--Hampton Roads--History.
United States. Army. Corps of Engineers--History.