In between the Tertiary rocks of the north, and the relatively new sediments along the coast, is a vast belt known as the Pleistocene Terraces.
Their age and distribution can be largely related to the rise and fall of sea levels during past ice ages.
Louisiana's capital is Baton Rouge and its largest city is New Orleans. The largest parish by population is East Baton Rouge Parish, and the largest by total area is Plaquemines.
Louisiana is bordered by Arkansas to the north, Mississippi to the east, Texas to the west, and the Gulf of Mexico to the south.
Before the American purchase of the territory in 1803, the current Louisiana State had been both a French colony and for a brief period, a Spanish one.
This area lies principally along the Gulf of Mexico and the Mississippi River, which traverses the state from north to south for a distance of about 600 miles (1,000 km) and empties into the Gulf of Mexico; the Red River; the Ouachita River and its branches; and other minor streams (some of which are called bayous).
Louisiana is bordered to the west by Texas; to the north by Arkansas; to the east by Mississippi; and to the south by the Gulf of Mexico.
The state may properly be divided into two parts, the uplands of the north, and the alluvial along the coast.
The breadth of the alluvial region along the Mississippi is from 10 to 60 miles (15 to 100 km), and along the other rivers, the alluvial region averages about 10 miles (15 km) across.
The Mississippi River flows along a ridge formed by its own natural deposits (known as a levee), from which the lands decline toward a river beyond at an average fall of six feet per mile (3 m/km).
There has never been an official language in Louisiana, and the state constitution enumerates "the right of the people to preserve, foster, and promote their respective historic, linguistic, and cultural origins," whether English, French, Spanish, or otherwise.