The Construction of Fort Miles

As war clouds gathered in the late 1930s, the Army began building Fort Miles, a massive coastal defense system at the entrance to the Delaware River and Bay. Its main batteries and headquarters stood at Cape Henlopen, Delaware, near the main shipping channel, while a supporting battery and lookout towers were placed on the Cape May side of the bay. Fort Miles was intended to protect the strategic industrial centers along this waterway, including the DuPont munitions and chemical plants in Wilmington, oil refineries in Chester, and shipyards in Philadelphia and Camden. Under a nationwide Harbor Defense Modernization plan, the Army Corps of Engineers began pouring eleven-foot-thick concrete emplacements in 1940 for a pair of 16-inch guns that were to serve as the fortification’s primary weapons. The plan also included five additional batteries, among them a 12-inch battery, two 6-inch support batteries, and a 6-inch battery on the Cape May side. Together with minefields, patrol boats, and airplanes, these defenses protected the Delaware River and Bay from enemy invasion.

New Jersey · United States