Fort Carroll is a
artificial island and abandoned hexagonal
sea fort
300px, Castillo San Felipe de Barajas in Cartagena de Indias, Colombia, an example of an Early Modern coastal defense
Coastal defence (or defense) and coastal fortification are measures taken to provide protection against military attack at or ...
in the middle of the
Patapsco River
The Patapsco River mainstem is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map , accessed April 1, 2011 river in central Maryland that flows into the Chesapeake Bay. The river's tidal port ...
, just south of
Baltimore, Maryland
Baltimore ( , locally: or ) is the most populous city in the U.S. state of Maryland, fourth most populous city in the Mid-Atlantic, and the 30th most populous city in the United States with a population of 585,708 in 2020. Baltimore was ...
. It is named for
Charles Carroll of Carrollton (1737–1832), a signer of the
Declaration of Independence.
Design and construction
In 1847, the State of Maryland gave permission to the United States War Department to construct a fort in the shallow water of Soller's Point Flats to protect the city of Baltimore. Fort Carroll was important for the defense of Baltimore—before the fort's construction,
Fort McHenry just outside the city was the only military defensive structure between Baltimore and the
Chesapeake Bay. The fort was part of the "Permanent System" or
Third System construction program, which aimed to defend America's most important ports.
Then Brevet-Colonel
Robert E. Lee
Robert Edward Lee (January 19, 1807 – October 12, 1870) was a Confederate general during the American Civil War, towards the end of which he was appointed the overall commander of the Confederate States Army. He led the Army of Nort ...
designed the hexagonal structure and supervised the construction, which the
U.S. Army Corps of Engineers commenced in 1848. The fort received its name on 8 October 1850. In 1852, Lee left Baltimore to become Superintendent of the
United States Military Academy at West Point.
In 1853 a
lighthouse
A lighthouse is a tower, building, or other type of physical structure designed to emit light from a system of lamps and lenses and to serve as a beacon for navigational aid, for maritime pilots at sea or on inland waterways.
Lighthouses mar ...
, now abandoned, was built on the ramparts to aid navigation into Baltimore Harbor. In 1898 a new lighthouse was built, the one still seen today. It was automated in 1920 and discontinued operations before 1945.
The original design foresaw the fort being armed with some 225 cannon on three levels. However, in April 1861 at the outbreak of the
Civil War, Fort Carroll's walls were still less than half the planned height of thirty feet. Only five gun platforms were ready and only two were armed with guns. Still, the Army emplaced about thirty cannon and occupied the fort throughout the war. In April 1864 torrential rains flooded the fort's magazines, which led the Army to move all the powder and ammunition to Fort McHenry.
Spanish–American War
When the United States entered into the
Spanish–American War in 1898, the Army again defended the fort, although the batteries by then were completely obsolete. The Army therefore commenced the construction of modern concrete gun emplacements following the designs of the
Endicott Board. The Army created three batteries: Battery Towson
[The battery was named in honor of Major General ]Nathan Towson
Nathaniel Towson (; January 22, 1784 July 20, 1854), also known as Nathan Towson, was a brevet major general in the United States Army. A career soldier, he fought in the War of 1812 as an artillery officer. He served as paymaster of the Army ...
, U.S. Army. He had served in the War of 1812 and the Mexican War and died July 20, 1854 at Washington, District of Columbia. (two 12"
barbette carriage guns), Battery Heart
[The battery was named in honor of Major Jonathan Heart, 2nd U.S. Infantry, who served during the Revolutionary War. He died on 4 November 1791 in action with Indians near Fort Recovery, Ohio.] (two
5-inch M1897 guns on
balanced pillar
A disappearing gun, a gun mounted on a ''disappearing carriage'', is an obsolete type of artillery which enabled a gun to hide from direct fire and observation. The overwhelming majority of carriage designs enabled the gun to rotate back ...
mounts) and Battery Augustin
[Battery Augustin was named in honor of 2nd Lieutenant Joseph N. Augustin, Jr., 24th U.S. Infantry, who died 2 July 1898 of wounds he had received the day before at the Battle of San Juan Hill.] (two 3" balanced pedestal-mount guns).

The new batteries were ready by September 1900, well after the end of the war. They received their names on 30 March 1903.
World War I and abandonment
After World War I broke out, in 1917 the Army removed the guns from Battery Heart and in 1918 those from Battery Towson to use elsewhere. By 1920, all guns had been removed from the fort.
In March 1921 the Army officially abandoned Fort Carroll and moved whatever military equipment was left to nearby
Fort Howard. The
War Department declared the island excess property in 1923, but took no immediate steps to sell the land. A variety of proposals for the use of the island were advanced, including a prison, as well as a 1923 plan advanced by Baltimore mayor
William Broening
William Frederick Broening (1870–1953) was a Maryland politician and twice Mayor of Baltimore (1919–1923, 1927–1931).
Background
William Frederick Broening was born in Baltimore, Maryland on 2 June 1870, the son of Henry Jacob Broening and ...
to place an electric "Welcome to Baltimore" sign on the island, accompanied by a statue of
Lord Baltimore.
In World War II the Army used the fort as a firing range. It also served as a checkpoint for vessels.
In May 1958, Baltimore attorney Benjamin Eisenberg purchased the island for , intending to put a casino there, but development plans never materialized.
The fort is now deserted and the habitat for various animals. It is also a site for occasional urban explorations. In 2013, Preservation Maryland placed Fort Carroll on its list of threatened historic properties.
It was listed on the
National Register of Historic Places in 2015.
References
Notes
Further reading
*
*
External links
A visit to Fort CarrollFort Carroll seen from the Key Bridge
{{authority control
Artificial islands of the United States
Infrastructure completed in 1848
Unused buildings in Maryland
Buildings and structures in Baltimore County, Maryland
River islands of Maryland
Carroll
Landforms of Baltimore County, Maryland
Carroll
Carroll
Robert E. Lee
National Register of Historic Places in Baltimore County, Maryland
American Civil War on the National Register of Historic Places