Fort Carroll is a artificial island and abandoned hexagonal sea fort in the middle of the Patapsco River, just south of Baltimore, Maryland. 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 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, 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 (two 12" barbette carriage guns), Battery Heart (two 5-inch M1897 guns on balanced pillar mounts) and Battery Augustin (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