This immense city always has something interesting or unusual going on, like this Urban Library (Biblioteca Urbana) project, on a busy street in the historic centre. The idea is simple, and it's been done in other countries before - you donate a book, you take one for reading. Once you're done reading, you return the book. In general, there is nobody guarding the library, and its success and survival is up to the city's citizens.
When we passed by, the project had been running for just a couple of days. Books filled every possible space and people were really excited! And who wouldn't! What a fantastic idea, right?
A couple of weeks later, we passed by again. Sadly, the library was almost empty - it had apparently fallen prey to people who didn't care to donate a book before taking one, and/or who couldn't bother to return those they'd read. Before posting this, I checked Twitter for their hashtag #Bibliotecaurbana. The pictures show the library had remained basically empty for about a week until a donation, today, by the Colegio Suizo (Swiss College).
Time will tell if this city's citizens allow this space to survive as a public library, or if it turns into a free-for-all bookshop stocked regularly by citizens concerned about the evident failure of the project.