Standing Guard

Built from 1939 to 1942, the concrete observation towers along Delaware's coast formed part of the coastal defenses protecting the entrance to Delaware Bay during World War II. The army built Fort Miles at Cape Henlopen to defend Wilmington and Philadelphia, while the towers served as spotters for the fort's heavy guns and worked with an underwater minefield stretching from Cape Henlopen to Cape May. Thirteen towers were constructed in all, with eleven along Delaware beaches from Fenwick Island to Cape Henlopen and two near Cape May, New Jersey. Equipped with optical instruments such as azimuth sighting range finders, the towers' observers tracked enemy warships by taking readings and sending coordinates to a base station or gun battery, where triangulation was used to determine artillery direction. The towers themselves were reinforced concrete structures built on pilings driven into the sand, intended to last about 20 years but still standing after 60, though abandoned since the early 1960s. They were never armed themselves, and the guns of Fort Miles were never called upon to fire at an enemy ship.

Delaware · United States