A naval mine is a self-contained explosive device placed in water to damage or destroy surface ships or submarines. Unlike depth charges, mines are deposited and left to wait until they are triggered by the approach of, or contact with, any vessel or a particular vessel type, akin to anti-infantry or anti-vehicle mines. Naval mines can be used offensively, to hamper enemy shipping movements or lock vessels into a harbour; or defensively, to protect friendly vessels and create "safe" zones. Mines allow the minelaying force commander to concentrate warships or defensive assets in mine-free areas giving the adversary three choices: undertake an expensive and time-consuming minesweeping effort, accept the casualties of challenging the minefield, or use the unmined waters where the greatest concentration of enemy firepower will be encountered.
Fort Schuyler is a preserved 19th century fortification in the New York City borough of the Bronx. It houses a museum, the Stephen B. Luce Library, and the Marine Transportation Department and Administrative offices of the State University of New York Maritime College. It is considered one of the finest examples of early 19th century fortifications. The fort was named in honor of Major General Philip Schuyler of the Continental Army.
Fort Totten is a former active United States Army installation in the New York City borough of Queens. It is located on the Willets Point peninsula on the north shore of Long Island. Fort Totten is at the head of Little Neck Bay, where the East River widens to become Long Island Sound. While the U.S. Army Reserve continues to maintain a presence at the fort, the property is now owned by the City of New York.
Fort Miles was a United States Army World War II installation located on Cape Henlopen near Lewes, Delaware. Although funds to build the fort were approved in 1934, it was 1938 before construction began on the fort. On 3 June 1941 it was named for Lieutenant General Nelson A. Miles.
Several boards have been appointed by US presidents or Congress to evaluate the US defensive fortifications, primarily coastal defenses near strategically important harbors on the US shores, its territories, and its protectorates.
Seacoast defense was a major concern for the United States from its independence until World War II. Before airplanes, many of America's enemies could only reach it from the sea, making coastal forts an economical alternative to standing armies or a large navy. After the 1940s, it was recognized that fixed fortifications were obsolete and ineffective against aircraft and missiles. However, in prior eras foreign fleets were a realistic threat, and substantial fortifications were built at key locations, especially protecting major harbors.
Fort Wetherill is a former coast artillery fort that occupies the southern portion of the eastern tip of Conanicut Island in Jamestown, Rhode Island. It sits atop high granite cliffs, overlooking the entrance to Narragansett Bay. Fort Dumpling from the American Revolutionary War occupied the site until it was built over by Fort Wetherill. Wetherill was deactivated and turned over to the State of Rhode Island after World War II and is now operated as Fort Wetherill State Park, a 51-acre (210,000 m2) reservation managed by the Rhode Island Department of Environmental Management.
Brewster Islands Military Reservation was a coastal defense site located on Great Brewster Island and Outer Brewster Island in Boston Harbor, Massachusetts as part of the Harbor Defenses of Boston.
The U.S. Army Mine Planter Service (AMPS) was an outgrowth of civilian crewed Army mine planter ships dating back to 1904. It was established on July 22, 1918 by War Department Bulletin 43 and placed the Mine Planter Service under the U.S. Army Coast Artillery Corps. Its purview was to install and maintain the underwater minefields that were part of the principal armament of U.S. coastal fortifications, including those at the approaches to the Panama Canal and the defenses of Manila Bay in the Philippines.
Camanche (ACM-11/MMA-11) was the name given in 1945 to the former U.S. Army Mine Planter (USAMP) Brigadier General Royal T. Frank (MP-12) while in naval inactive reserve more than ten years after acquisition of the ship by Navy from the Army in 1944. The ship had previously been classified by the Navy as an Auxiliary Mine Layer (ACM) and then Minelayer, Auxiliary (MMA). The ship was never commissioned by Navy and thus never bore the "USS" prefix.
Mine planter and the earlier "torpedo planter" was a term used for mine warfare ships into the early days of World War I. In later terminology, particularly in the United States, a mine planter was a ship specifically designed to install controlled mines or contact mines in coastal fortifications. This type of ship diverged in both function and design from a ship operating as a naval minelayer. Though the vessel may be seagoing it is not designed to lay large numbers of mines in open sea. A mine planter was designed to place controlled minefields in exact locations so that they might be fired individually or as a group from shore when observers noted a target to be at or near a designated mine's position. The terms and types of specialized ship existed from the 1860s where "torpedoes" were made famous in the American Civil War until the demise of large, fixed coastal fortifications brought on by the changes of World War II.
The modern era of defending American harbors with controlled mines or submarine mines began in the post-Civil War period, and was a major part of US harbor defenses from circa 1900 to 1947.
The U.S. Army Coast Artillery Corps (CAC) was an administrative corps responsible for coastal, harbor, and anti-aircraft defense of the United States and its possessions between 1901 and 1950. The CAC also operated heavy and railway artillery during World War I.
Fort Williams is a former United States Army fort in Cape Elizabeth, Maine which operated from 1872 to 1964. It was part of the Coast Defenses of Portland, later renamed the Harbor Defenses of Portland, a command which protected Portland's port and naval anchorage 1904–1950. After its closure, it was redeveloped into Fort Williams Park.
A Harbor Defense Command was a military organization of the United States Army Coast Artillery Corps designated in 1925 from predecessor organizations dating from circa 1895. It consisted of the forts, controlled underwater minefields, and other coastal defenses of a particular harbor or river. Harbor Defense Commands, along with the similar Coast Artillery Corps, were disestablished in 1950.
Fort Foster, now part of Fort Foster Park, is a historic fort active 1901–1946 on the southwest tip of Gerrish Island in the Kittery Point area of Kittery, Maine. The park includes beaches and trails. Battery Bohlen and Battery Chapin were the major parts of the fort.
The Harbor Defenses of Portland was a United States Army Coast Artillery Corps harbor defense command. It coordinated the coast defenses of Portland, Maine, the mouth of the Kennebec River, and surrounding areas from 1895 to 1950, beginning with the Endicott program. These included both coast artillery forts and underwater minefields. The command originated circa 1895 as the Portland Artillery District, was renamed Coast Defenses of Portland in 1913, and again renamed Harbor Defenses of Portland in 1925.
The Harbor Defenses of Portsmouth was a United States Army Coast Artillery Corps harbor defense command. It coordinated the coast defenses of Portsmouth, New Hampshire and the nearby Portsmouth Naval Shipyard in Kittery, Maine from 1900 to 1950, both on the Piscataqua River, beginning with the Endicott program. These included both coast artillery forts and underwater minefields. The command originated circa 1900 as the Portsmouth Artillery District, was renamed Coast Defenses of Portsmouth in 1913, and again renamed Harbor Defenses of Portsmouth in 1925.
The depression range finder (DRF) was a fire control device used to determine the target's position by observing range and bearing and to calculate firing solutions when gun laying in coastal artillery. It was the main component of a vertical base rangefinding system. It was necessitated by the introduction of rifled artillery from the mid-19th century onwards, which had much greater ranges than the old smoothbore weapons and were consequently more difficult to aim accurately. The DRF was invented by Captain H.S.S. Watkin of the Royal Artillery in the 1870s and was adopted in 1881. It could provide both range and bearing information on a target. The device's inventor also developed a family of similar devices, among them the position finder, which used two telescopes as a horizontal base rangefinding system, around the same time; some of these were called electric position finders. Some position finders retained a depression range finding capability; some of these were called depression position finders. Watkin's family of devices were deployed in position finding cells, a type of fire control tower, often in configurations that allowed both horizontal base and vertical base rangefinding. Watkin's system included automatic electrical updating of range and bearing dials near the guns as the position finders were manipulated, and a system of remotely firing the guns electrically from the position finding cell. The improved system was trialled in 1885 and widely deployed in the 1890s. Functionally equivalent devices were developed for the United States Army Coast Artillery Corps and its predecessors, called depression position finders or azimuth instruments depending on function, adopted in 1896 and deployed widely beginning in the early 1900s as the Endicott program of modern coastal defences was built. These devices were also used by both countries to control submarine (underwater) minefields.
