Meeting of Favela 8 – one of the world’s biggest graffiti events, at Vila Operária, Duque de Caxias, which featured a mutirão (day of collective action) by hundreds of artists. Photo by Paulo Barros, December 1, 2013. Meeting of Favela 8 – one of the world’s biggest graffiti events, at Vila Operária, Duque de Caxias, which featured a mutirão (day of collective action) by hundreds of artists. Photo by Paulo Barros, December 1, 2013.