Built 1845–1853, it is a nationally significant example of Greek Revival architecture, and one of the finest works of architect James Gallier.

Gallier Hall is located on St. Charles Avenue at Lafayette Square in the Central Business District.

Gallier Hall is a three-story marble structure fronted by two rows of fluted Ionic columns in the Neoclassical style.

Many important events during the Civil War, Reconstruction, and the era of Louisiana governor Huey Long took place at Gallier Hall.

On Mardi Gras Day the mayor of New Orleans toasts the kings of the Zulu Social Aid & Pleasure Club and Rex Parade here.