Louisiana is a state located in the southern region of the United States. Louisiana is the 31st most extensive and the 25th most populous of the 50 United States. Its capital is Baton Rouge and largest city is New Orleans. Louisiana is the only state in the U.S. with political subdivisions termed parishes, which are local governments equivalent to counties. The largest parish by population is East Baton Rouge Parish, and the largest by land area is Cameron Parish.
Much of the state's lands were formed from sediment washed down the Mississippi River, leaving enormous deltas and vast areas of coastal marsh and swamp. The two "Deltas" are located in Monroe, the parish seat of Ouachita Parish, Shreveport, the parish seat of Caddo Parish, and Alexandria, the parish seat of Rapides Parish, for the small Delta, and Monroe, Lake Charles, and New Orleans for the large Delta.