New Orleans (, , , or ; ) is a major United States port and the largest city and metropolitan area in the state of Louisiana. The population of the city was 343,829 as of the 2010 U.S. Census. The New Orleans metropolitan area (New Orleans–Metairie–Kenner Metropolitan Statistical Area) had a population of 1,167,764 in 2010 and was the 46th largest in the United States. The New Orleans–Metairie–Bogalusa Combined Statistical Area, a larger trading area, had a 2010 population of 1,452,502. The city is named after the Duke of Orleans, who reigned as Regent for Louis XV from 1715 to 1723, as it was established by French colonists and strongly influenced by their European culture. It is well known for its distinct French and Spanish Creole architecture, as well as its cross-cultural and multilingual heritage. New Orleans is also famous for its cuisine, music (particularly as the birthplace of jazz), and its annual celebrations and festivals, most notably Mardi Gras, dating to French colonial times. The city is often referred to as the “most unique”The term “most unique” is grammatically incorrect, as the word “unique” is a superlative. See for example: Merriam-Webster Dictionary of American Usage, Springfield, Massachusetts: Merriam-Webster, Inc., 1994. Fowler, Henry, A Dictionary of Modern English Usage, Oxford: Oxford University Press, USA, 2003. Nicholson, Margaret, A Dictionary of American English Usage, New York: Oxford University Press, 1957. in the United States. New Orleans is located in southeastern Louisiana, straddling the Mississippi River. The city and Orleans Parish () are coterminous. The city and parish are bounded by the parishes of St. Tammany to the north, St. Bernard to the east, Plaquemines to the south, and Jefferson to the south and west. Lake Pontchartrain, part of which is included in the city limits, lies to the north and Lake Borgne lies to the east. Before Hurricane Katrina, Orleans Parish was the most populous parish in Louisiana. It now ranks third in population behind neighboring Jefferson Parish and East Baton Rouge Parish.