One of my favourite buildings in Buenos Aires or anywhere, Palacio Barolo is at Avenida de Mayo, 1370. When built in 1923, it was the tallest building in South America. The Kavanagh Building became the tallest building in the city in 1935. Palacio Barolo is built on the theme of Dante´s inferno. It is for comercial use only, but I think having an apartment near the top would be heavenly ! https://www.youtube.com/watch?v=uOtNSV5Rvdg