This site at the confluence of the Potomac and Anacostia rivers has been in use since the 1790s, when a battery and official reservation were situated at Greenleaf Point. During the nineteenth century, a federal prison was located on the grounds and the Lincoln conspirators were hanged there. As other military installations developed in the region, the functions of this site were transferred to locations farther from the center of the city, and the Army War College (now National War College) was established. As an outgrowth of his work on the 1901–1902 McMillan Plan, Charles McKim provided the plan and architectural form. Later the National War College became part of the National Defense University.
Closest to the Fort McNair entrance, tightly packed brick buildings house barracks for enlisted persons and support services. The dense geometrically arranged cluster on either side of a north-south thoroughfare opens into the expansive parade ground that runs south to the National War College building. This vista is punctuated, some say spoiled, by two penitentiary buildings adapted to the needs of the installation. East of the parade ground is a row of noncommissioned officers' quarters, all identical brick duplex houses. West of the parade ground, with scenic views of the Washington Channel, Hains Point, the Potomac River, and the Virginia shore, is a row of officers' quarters—large, detached, single-family houses that reflect their occupants' rank. The penultimate building is the domed National War College with its great interior vaults fashioned of Guastavino tile. The design and composition of the final academic building at the center of the U-shaped configuration of residences invoke Thomas Jefferson's University of Virginia and his love of Roman forms. A pleasant tree-lined promenade encircles the site at the water's edge.