Fort Washington, 1814-1872, defended the Potomac River approach to Washington, DC during the Mexican War and the American Civil War. The first Fort Washington was completed in 1809 and guarded the Nation’s Capital until it was destroyed by its own garrison in 1814. Twelve days later Major Pierre L’Enfant was sent to construct new defenses but worked on the fort for only a brief period before Lieutenant Colonel Walker K. Armistead replaced him. The fort was completed on October 2, 1824. Extensive remodeling was performed in the 1840s and the first guns were mounted in 1846. The masonry fort was occupied by soldiers from the First, Third and Fourth U.S. Artillery during its early history. Except for a few guns at the Washington Arsenal, Fort Washington was the only defense for the Nation’s Capital until the Civil War when a circle of temporary forts was built around the city. Battery Rogers and Fort Foote were the only seacoast forts in the system and armed with large Rodman and Parrott cannons. Fort Washington was garrisoned as the outer defense for the city. Companies of the First and Fourth Artillery as well as numerous state artillery units passed through the post during the war. ( Source - National Park Service
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