As the Traveler points out, Buenos Aires is pretty cheap for most foreigners anyways ($1 equals about 3 1/2 Argentine pesos as of today, 4.8 for one British pound) but for the real cheapskate, myself included (not by choice) BA has a ton of things to see and do for approximately zero dollars/pounds/pesos.
One of South America’s (and the world’s) premier museums, Museo Nacional de Bellas Artes (Museum of Fine Arts) is free every day of the week, which is good since it will likely take you more than one day to see everything it has to offer.
The article also mentions a free guided tour from a group called BA Free Tours who offer free tours, one at 11 a.m. and one at 5 p.m. (Notice the late starting time? Gives you an idea of the nightlife in the city — something you will have to shell out some money for.)
I have to admit, I have an unnatural fondness for Botanical Gardens (see my Medellín video) but BA’s Jardín Botánico Carlos Thays takes it to the next level. Even better, it’s located directly next to the neighborhood of Palermo which means you’re about a five minute walk from where you’re probably sleeping — perfect for rolling out of bed and wandering to after a long night out. I’m just saying.
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