Buenos Aires, officially the Autonomous City of Buenos Aires, is the capital and largest city of Argentina. It is located on the southwest of the Río de la Plata. Buenos Aires is classified as an Alpha− global city, according to the Globalization and World Cities Research Network (GaWC) 2024 ranking. The city proper has a population of 3.1 million and its urban area 16.7 million, making it the fourteenth largest metropolitan area in the world. The proper city of Buenos Aires is neither part of Buenos Aires Province nor its capital; it is an autonomous district.
https://en.wikipedia.org/wiki/Buenos_Aires