Buenos Aires (Spanish pronunciation: [ˈbwenoˈsaiɾes]) is the capital and largest city of Argentina, currently the second-largest metropolitan area in South America, after São Paulo. It is located on the western shore of the estuary of the Río de la Plata, on the southeastern coast of the South American continent. The city of Buenos Aires is not part of Buenos Aires Province, nor is it its capital; rather, it is an autonomous federal district. Greater Buenos Aires is the third-largest conurbation in Latin America, with a population of around 13 million. Buenos Aires is considered an Alpha World City listed by the Loughborough University group's (GaWC) 2008 inventory.

After the internal conflicts of the 19th century, Buenos Aires was federalised and removed from Buenos Aires Province in 1880. The city limits were enlarged to include the former towns of Belgrano and Flores, which are both now neighbourhoods of the city.

Buenos Aires (English: Fair Winds or Good Air (see Names of Buenos Aires)) was originally named after the sanctuary of "Nostra Signora di Bonaria" (Italian for "Our Lady of Bonaria") in Cagliari, Sardinia. In the 1994 constitution the city became autonomous, hence its formal name: Ciudad Autónoma de Buenos Aires, in English, Autonomous City of Buenos Aires. People from Buenos Aires are referred to as porteños (people of the port).From:wikipedia.org