Fort Casey State Park is located on
Whidbey Island in
Washington state.
Admiralty Inlet was considered so strategic to the defense of
Puget Sound in the 1890s that three forts, Fort Casey on Whidbey Island,
Fort Flagler on
Marrowstone Island, and
Fort Worden at Port Townsend, were built at the entrance with huge guns creating a "Triangle of Fire." This military strategy was built on the theory that the three fortresses would thwart any invasion attempt by sea. Fort Casey is now a 467 acres (1.89 km2) marine camping park.
Designed as part of the massive modernization program of U.S. seacoast fortifications initiated by the
Endicott Board, construction on Fort Casey began in 1897. In 1901, her big
guns on disappearing carriages, which could be raised out of their protective emplacements so that the guns were exposed only long enough to fire, became active. However, the fort's ammunition batteries became obsolete almost as soon as their construction was completed.
The invention of the airplane in 1903, and the subsequent development of military aircraft made the fort vulnerable to air attack. In addition, the development of battleships designed with increasingly accurate weaponry transformed the static strategies of the nineteenth century into the more mobile attack systems of the twentieth century.
Most of Fort Casey's guns and mortars were removed and sent to Europe and the Pacific during
World War I, where they were mounted on railcars to serve as mobile heavy artillery.
In 1935, the
Coast Artillery withdrew the station's battery assignments and placed it on inactive status. As
World War II approached, military officials reactivated Fort Casey after making physical improvements to the aging frame-plaster construction.
Two of the fort's 10-inch (25-cm) seacoast artillery guns on their carriages were salvaged in the mid-1960s from their final active duty location at
Fort Wint on the
U. S. Naval Base Subic Bay. The guns showed visible shrapnel scarring from the effects of the Japanese bombings in the Philippines at the opening of World War II. Two 3-inch (76-mm) rapid-fire guns from Fort Wint are also mounted at Fort Casey.
