Buenos Aires  is the capital and largest city of Argentina, and the second-largest metropolitan area in South America. It is located on the western shore of the estuary of the Río de la Plata, on the continent's southeastern coast. The Greater Buenos Aires conurbation, which also includes several Buenos Aires Province districts, constitutes the third-largest conurbation in Latin America, with a population of around fifteen and a half million.

The city of Buenos Aires is neither part of Buenos Aires Province nor the Province's capital; rather, it is an autonomous district.  In 1880, after decades of political infighting, Buenos Aires was federalized and removed from Buenos Aires Province.The city limits were enlarged to include the towns of Belgrano and Flores; both are now neighborhoods of the city. The 1994 constitutional amendment granted the city autonomy, hence its formal name: Ciudad Autónoma de Buenos Aires (Autonomous City of Buenos Aires). Its citizens first elected a chief of government (i.e. mayor) in 1996; before, the mayor was directly appointed by the President of the Republic.

Buenos Aires is, along with Mexico City and São Paulo, one of the three Latin American cities considered an 'alpha city' by the study GaWC5. Buenos Aires' quality of life was ranked 81st in the world and one of the best in Latin America in 2012, with its per capita income among the three highest in the region. It is the most visited city in South America (ahead of Rio de Janeiro) and the second most visited city of Latin America (behind Mexico City).

Buenos Aires is a top tourist destination,  and is known for its European-style architecture  and rich cultural life. Buenos Aires held the 1st Pan American Games in 1951 as well as hosting two venues in the 1978 FIFA World Cup. Buenos Aires will host the 2018 Summer Youth Olympics.

Buenos Aires defines itself as a multicultural city, being home to multiple ethnic and religious groups. Also, several languages are spoken in the city in addition to Spanish, contributing to its culture and the dialect spoken in the city and in some other parts of the country. This is because in the last 150 years the city, and the country in general, has been a major recipient of millions of immigrants from around the world, especially from Europe, Asia and Latin America, making it a melting pot where several ethnic groups live together and being considered as one of the most diverse cities in Latin America.

Country      Argentina
Established     1536, 1580
 
Area
 • City     203 km2 (78 sq mi)
 • Land     203 km2 (78.5 sq mi)
 • Metro     4,758 km2 (1,837 sq mi)
Elevation     25 m (82 ft)

Population (2015 census.)
 • City     3,090,922
 • Rank     1st
 • Density     15,000/km2 (39,000/sq mi)
 • Metro     12,741,364