Participatory Monumental Construction by Olivier Grossetête

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Details · From the poster
Participa en la construcción monumental del artista francés en el Predio Polo Circo durante La Noche de los Museos.
A guess
An afternoon: a quiet, curious mood, with things to look at and talk about afterwards. Probably people who enjoy culture, often one or two friends together. In Buenos Aires people dine late and go out after 23:00.
A guess from the kind of event, the hour and the city, not from the organizer.