7. Built by a young Robert E. Lee, Fort Carroll was ordered and repeatedly re-modernized by the U.S. Army over decades despite never actually fulfilling its defensive purpose
Named for Charles Carroll, the last surviving signatory to the Declaration of Independence, Fort Carroll is a small artificial island located in the Patapsco River south of Baltimore, Maryland. Housing a now-abandoned hexagonal sea fort, the 3.4-acre island was ordered in 1847 on the instructions of the United States War Department as part of the “Third System” strategy: a program aiming to increase protections for America’s most vulnerable but nevertheless vital ports. Designed by then Brevet-Colonel Robert E. Lee, the future General-in-Chief of the Confederate States of America, construction was concluded in 1852.
Seeing no action during the Civil War, and with its magazines flooded in 1864 by heavy rains, the outbreak of the Spanish-American War in 1898 saw the Army undertake a costly modernization of the fort. However, once again, the war was over long-before modifications were complete in 1900. Removing the batteries during World War I, in 1921 the Army officially abandoned Fort Carroll and the War Department declared the island excess property two years later. Vacant for decades, in 1958 the island was sold to Benjamin Eisenberg for $10,000 whose plans to build a casino, like the Army’s hopes for the fort, never materialized.