Buenos Aires is the capital city of Argentina.He stands on the widest river in the world.Its population of 3 million or 10 including Gran Buenos Aires . It is a large shopping center with nice shops.Buenos Aires was a small port in the Spanish Empire. Took independence in 1816. The city developed rapidly.Tango dancing began to be performed in the 19th century. Dancers are very long practiced on the streets before dancing with a woman. Now there are many tango bars,where tourists come. Astor Piazzolla, the famous composer of modern tango, lived there until his death in 1992.