The Louisiana's Old State Capitol is a historic government building, and now a museum, at 100 North Boulevard in Baton Rouge, Louisiana, U.S.A.. Built in which housed the Louisiana State Legislature from the mid-19th century until the current capitol tower building was constructed in 1929-32.
It was built to both look like and function like a castle and has led some locals to call it the Louisiana Castle, the Castle of Baton Rouge, the Castle on the River, or the Museum of Political History; although most people just call it the old capitol building. The term "Old State Capitol" in Louisiana is used to refer to the building and not to the two towns that were formerly the capital city: New Orleans and Donaldsonville. It was designated a National Historic Landmark in 1974 for its architecture.