Pentagon Barracks, Baton Rouge

Pentagon Barracks is a group of historic buildings constructed between 1819 and about 1825, after the United States took control of the area. The site was planned by U.S. Army officer Captain James Gadsden as housing for around 1,000 troops. It originally had five buildings arranged in a pentagon around a courtyard. The fifth building, used as a commissary and warehouse, was removed soon after its completion in the early 1820s due to poor construction, leaving four buildings today.

The buildings are two-story brick structures with hipped roofs. Covered galleries with columns were added later, first along the courtyard side and then extended to the outer facades in 1834. These walkways provide shade and protection from rain. All buildings face inward toward the courtyard, which once served as a parade ground and a shared space for daily routines.

The barracks remained an active military post until 1879, including use during the Civil War by both Union and Confederate forces. From 1886 to 1925, Louisiana State University used the buildings as dormitories and classrooms. Today, they function as private apartments for state legislators and offices for the Lieutenant Governor, and a small museum on site presents the history of the complex.