Buenos Aires looks like Paris and Madrid and Milan got stuck in a traffic jam on the edge of South America. Millions of European immigrants, many of them Italian, arrived over the decades and built a capital in their own image: a 1908 opera house, a café from 1858, an avenue 110 metres wide. Then came the coups, the crashes and the currency crises, and the same city learned to improvise. You see both at once, a gilded theater and a street where someone is grilling sausages for a football crowd.
It is a city of barrios, forty-eight of them, and each has its own habits. San Telmo has the cobbles and the Sunday fair, La Boca has the colors and the football, Recoleta has the cemetery and the money, Palermo has the parks and the bars. Porteños, as locals call themselves, eat dinner at 10 pm and sit over a coffee for an hour, which is why five days is the right length.
The plan groups the barrios so you rarely cross the city twice. Day one is the center around Plaza de Mayo, day two San Telmo, La Boca and the docks, day three Recoleta and Palermo, day four the ferry to Colonia del Sacramento in Uruguay, and day five museums, Palermo's streets and a night of football or milonga. Start on a Saturday: the San Telmo fair runs only on Sundays, the Bellas Artes museum is closed on Mondays, and the Teatro Colón tour runs daily. Read the Argentina country page for the bigger picture, and look at the money section in the tips before you land, because paying in Argentina works differently from anywhere else right now.