What is the capital of Argentina?

Buenos Aires sits on the southwestern shore of the Río de la Plata, the wide estuary that separates Argentina from Uruguay, which historically made it the country's main Atlantic port.

Buenos Aires is the capital and seat of government of Argentina, a role it has held since 1880. Argentina itself has an estimated population of 45,851,378 (2025).

Buenos Aires is also the largest city in Argentina, which is the usual arrangement, though it is far from universal: see the countries where capital and largest city differ.

The site was first settled in 1536 by Pedro de Mendoza, abandoned, then permanently re-established in 1580 by Juan de Garay.

Buenos Aires has been the capital of Argentina since 1880, the city was formally federalised as the seat of Argentina's national government, ending decades of conflict between Buenos Aires and the interior provinces.

Paraná, in Entre Ríos province, served as the capital of the breakaway Argentine Confederation from 1853 to 1861, while Buenos Aires was temporarily separated from the rest of the country.

Buenos Aires is by far the most populous city in Argentina, and its metropolitan area is home to roughly a third of the country's entire population.

Its residents are known as porteños, meaning 'people of the port', a nod to the city's origins on the Río de la Plata waterfront.

The city is the political, financial and cultural centre of Argentina and one of the largest metropolitan areas in South America.

Its best-known landmarks include the Plaza de Mayo, the Casa Rosada presidential palace and the Teatro Colón opera house.

City facts sourced from Wikipedia: Buenos Aires.

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