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 (English: Autonomous City of Buenos Aires).
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. It is the second most visited city across Spanish Latin America (behind Mexico City). It is also one of the most important, largest and most populous of South American capitals.
Buenos Aires is known for its European-style architecture, with the highest concentration of theaters in the world. People from Buenos Aires are referred to as Porteños (people of the port).