Old Louisiana State Capitol, Gothic Revival government building in downtown Baton Rouge, United States.

The Old Louisiana State Capitol is a Gothic Revival museum building in downtown Baton Rouge with pointed towers and stained glass windows. The facade shows crenellations and arches, while inside a winding staircase leads to several exhibition rooms.

In 1846 the legislature voted to move the seat of government from New Orleans to Baton Rouge, and in 1847 the city donated a $20,000 parcel on a bluff above the Mississippi. New York architect James H. Dakin designed a Neo-Gothic castle rather than copy the national Capitol. Union troops used it as a prison and garrison during the Civil War, and it burned twice. William A. Freret rebuilt it by 1882, adding the spiral staircase and stained glass dome; it was restored in the 1990s.

The name reflects its role as a government center, and today the rooms display posters and prints about statewide elections. Visitors can walk between the halls and see old writing desks and assembly benches from the 19th century.

The building stands at 100 North Boulevard on a bluff above the Mississippi River, within walking distance of the current capitol tower, the Old Governor's Mansion, St. Joseph Cathedral and the Shaw Center. Admission is free and the building is wheelchair-accessible. The Ghost of the Castle, a roughly 12-minute theatrical production, is part of the visitor experience.

The stained glass dome was installed by engineer William A. Freret when he rebuilt the gutted statehouse by 1882, not in the 1970s. Look up into the octagonal dome: a wheel of pale panes ringed by bands of blue, red, yellow and green squares, bordered by gold leaf molding above dark wood tracery.